Shop deutz engine

Sponsored
About our ads
$7,268.88
Engine Assembly For Deutz Engine TD2.9 L4
Fridayparts.com
$7,268.88
Engine Assembly For Deutz Engine TD2.9 L4
Fridayparts.com
$20,520.00
Engine Assembly Air Cooled F2L912 2 Cylinder 4 Stroke For Deutz 912
eBay
Free shipping
$20,520.00
Engine Assembly Air Cooled F2L912 2 Cylinder 4 Stroke For Deutz 912
eBay
$616.00
NEW S100 Turbo Deutz BF3M2011 BF3L2011 2.33L Diesel Engine 04280664KZ 318195
TurboTurbos
$616.00
NEW S100 Turbo Deutz BF3M2011 BF3L2011 2.33L Diesel Engine 04280664KZ 318195
TurboTurbos
$8,189.99
53.7KW 2700Rpm/Min Engine Assembly For Deutz TD2011L041
Fridayparts.com
$8,189.99
53.7KW 2700Rpm/Min Engine Assembly For Deutz TD2011L041
Fridayparts.com
$11,900.00
NEW 2021 Deutz TCD3.6L4 Diesel Engine, Family MDZXL03.6060, 120HP, Tier 4Final
eBay
Free shipping
$11,900.00
NEW 2021 Deutz TCD3.6L4 Diesel Engine, Family MDZXL03.6060, 120HP, Tier 4Final
eBay
$23,091.99
74.4KW 2300Rpm/Min Engine Assembly For Deutz TCD3.6 L4
Fridayparts.com
$23,091.99
74.4KW 2300Rpm/Min Engine Assembly For Deutz TCD3.6 L4
Fridayparts.com
$16,600.00
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$16,600.00
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$16,830.08
Engine Assembly For Deutz D2011L03I
Fridayparts.com
$16,830.08
Engine Assembly For Deutz D2011L03I
Fridayparts.com
$13,919.20
Engine Assembly For Deutz BF6M1013FC
Fridayparts.com
$13,919.20
Engine Assembly For Deutz BF6M1013FC
Fridayparts.com
$13,798.50
Multiquip Genuine Part D2011L02I Engine Deutz 29.9 HP MQ62TDD
SLE Equipment
$13,798.50
Multiquip Genuine Part D2011L02I Engine Deutz 29.9 HP MQ62TDD
SLE Equipment
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6 Diesel Engine 53039880725
TurboTurbos
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6 Diesel Engine 53039880725
TurboTurbos
$33,774.14
Part 900-6035-30: Replacement Engine, Deutz Bf4l2011, 79Hp For 3200T | Bandit Industries
ModernEquipmentParts.com
$33,774.14
Part 900-6035-30: Replacement Engine, Deutz Bf4l2011, 79Hp For 3200T | Bandit Industries
ModernEquipmentParts.com
$10,868.00
D7E Engine Deutz 4 Engine Motor For Vplvo EC290 L04 2V C290 L04 2V D7D D6E D6D
eBay
Free shipping
$10,868.00
D7E Engine Deutz 4 Engine Motor For Vplvo EC290 L04 2V C290 L04 2V D7D D6E D6D
eBay
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6L Engine 53039880723
TurboTurbos
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6L Engine 53039880723
TurboTurbos
$10,926.80
JLG Part 1001251857 - ENGINE, DEUTZ LRC TD3.6L 100HP
Zuma Sales LLC Store PMAX
$10,926.80
JLG Part 1001251857 - ENGINE, DEUTZ LRC TD3.6L 100HP
Zuma Sales LLC Store PMAX
$1,195.00
NEW Borgwarner K27.2 Turbo Deutz Tractor Truck BF6L913 Diesel Engine 53279886409
TurboTurbos
$1,195.00
NEW Borgwarner K27.2 Turbo Deutz Tractor Truck BF6L913 Diesel Engine 53279886409
TurboTurbos
$10,646.00
Complete Deutz F4L 1011 F Engine, Genie S-60, S-65, JLG, 600S, 660SJ, Bobcat
eBay
$10,646.00
Complete Deutz F4L 1011 F Engine, Genie S-60, S-65, JLG, 600S, 660SJ, Bobcat
eBay
$795.00
S400 Turbo Deutz Industrial Gen Set BF6M1015CP COM2 Diesel Engine 319124 319192
TurboTurbos
$795.00
S400 Turbo Deutz Industrial Gen Set BF6M1015CP COM2 Diesel Engine 319124 319192
TurboTurbos
$24,310.00
JLG Part 1001148159XED - ENGINE, DEUTZ TD2.9
Zuma Sales LLC Store PMAX
$24,310.00
JLG Part 1001148159XED - ENGINE, DEUTZ TD2.9
Zuma Sales LLC Store PMAX
$13,453.02
Part 1001148076XED: JLG ENGINE, DEUTZ LRC TD3.6L 100HP
ModernEquipmentParts.com
$13,453.02
Part 1001148076XED: JLG ENGINE, DEUTZ LRC TD3.6L 100HP
ModernEquipmentParts.com
$2,900.00
Deutz D 2011 L 03 Air Cooled Diesel Engine 3 Cylinder
eBay
Free shipping
$2,900.00
Deutz D 2011 L 03 Air Cooled Diesel Engine 3 Cylinder
eBay
$15,262.22
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$15,262.22
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$10,250.00
New Deutz TCD3.6L4 Industrial Diesel Engine 95Kw @ 2200Rpm, 127Hp, Tier 4 Final
eBay
$10,250.00
New Deutz TCD3.6L4 Industrial Diesel Engine 95Kw @ 2200Rpm, 127Hp, Tier 4 Final
eBay
$9,995.00
New DEUTZ, F4L912 Engine Freight Included US48 Tag 70816
eBay
Free shipping
$9,995.00
New DEUTZ, F4L912 Engine Freight Included US48 Tag 70816
eBay
$4,895.00
Deutz TD2011 Engine Block
eBay
$4,895.00
Deutz TD2011 Engine Block
eBay
$3,090.00
Deutz 3 Cylinder Air Cooled Diesel Engine F3LW912W
eBay
$3,090.00
Deutz 3 Cylinder Air Cooled Diesel Engine F3LW912W
eBay
$450.95
New OEM Deutz Engine Kit 31013S1Z
eBay
Free shipping
$450.95
New OEM Deutz Engine Kit 31013S1Z
eBay
$11,900.00
Deutz F4L1011F Diesel Engine Family, YDZXL02.7018, 47HP, 2.73L, Engine Code: C35
eBay
$11,900.00
Deutz F4L1011F Diesel Engine Family, YDZXL02.7018, 47HP, 2.73L, Engine Code: C35
eBay
The ENTIRE History Of Deutz Engines
24:02
The ENTIRE History Of Deutz Engines
14.5K views7 months ago
YouTubeAmerican Vintage Lifestyle
Deutz Engine - How the engine works
1:40
Deutz Engine - How the engine works
146.5K viewsMar 1, 2007
YouTubeFantaCoke
WWII Deutz Engines That Survived Harshest Battlefields. German Diesel Power & Engineering.
20:54
WWII Deutz Engines That Survived Harshest Battlefields. German Diesel Power & Engineering.
5.6K views8 months ago
YouTubeFUTEK HD
Everything You Need to Know About a Deutz Air-Cooled Diesel
8:24
Everything You Need to Know About a Deutz Air-Cooled Diesel
315.1K viewsJul 23, 2019
YouTubeDEBOSS GARAGE
Complete Engine Assemble Reviving the Power – Complete Deutz Diesel Pump Setup Done
22:08
Complete Engine Assemble Reviving the Power – Complete Deutz Diesel Pump Setup Done
53K views5 months ago
YouTubeAfghan Mechanical Works
The Insane Truth About the Bizarre Deutz F4L912 Diesel Engine
15:33
The Insane Truth About the Bizarre Deutz F4L912 Diesel Engine
96K views8 months ago
YouTubeVintage American Machines
Incredible Reconstruction Deutz 4-Cylinder Diesel Engine || Restoration of Diesel Engine
35:58
Incredible Reconstruction Deutz 4-Cylinder Diesel Engine || Restoration of Diesel Engine
14K viewsDec 21, 2023
YouTubeMaster Mechanics
23:52
Why Deutz F6L912 Was KILLED | The AIR Cooled Engine
3.1K views3 months ago
YouTubeClassic American Machines
2:26
Meet the DEUTZ G2.9 Engine | Built for Demanding Applications
15 views3 months ago
YouTubeDEUTZ Corporation
14:57
The Deutz Engine That Silenced Perkins in 1978
21K views7 months ago
YouTubeVintage American Machines
0:22
Exploring the Deutz Turbo 8006: Features and Benefits
18.7K views3 months ago
TikTokboening01
0:15
Unleashing the Power of Deutz Engines
8.7K views2 months ago
TikTokdeutz06fahrn
20:13
Why the Deutz F6L912 Was BANNED – The Engine That Was Too Strong | Abdy moter
3 weeks ago
YouTubeabdy motors
1:12
Deutz-Fahr Tractor Evolution (1927-2023) | The Legendary Air-Cooled Giants! ShiftEvo
242.6K views1 month ago
YouTubeShiftEvo
24:49
When Ancient Diesel Engines Wake Up (1881–1950s) | Cold Start & First Run After Decades
17.4K views3 months ago
YouTubePOWER REBORN
6:33
The Diesel That Ruled the Seas – How Deutz Engines Conquered the Ocean
19 views6 months ago
YouTubeMotor Mythen
33:43
20 Shocking Secrets About Deutz F6L912 You Didn’t Know!
7.9K views8 months ago
YouTubeRare Old Engines
13:32
Why Deutz F3L912 Was Banned: The Engine That Was Too Powerful to Survive
5K views8 months ago
YouTubeEpic Motors
24:29
Legendary Slavia & Deutz Engines That Refuse to Die. A full history of vintage diesel power.
5.7K views7 months ago
YouTubeFUTEK HD
0:44
how to timing the deutz engine, #mechanic
1.1K views4 months ago
YouTubeRD Mix Vlog
16:24
Why Deutz F8L413F Was Banned: The Engine That Pushed Boundaries Too Far
7.3K views8 months ago
YouTubeEpic Motors
16:59
Magirus-Deutz: Why Did These Super Trucks That Feared Neither Cold Nor Off-Road Disappear?
41.8K views1 month ago
YouTubeSpace of car history
18:11
Why Deutz F4L912 Was Banned: Too Strong For It's Own Good
32.4K views8 months ago
YouTubeAmerican Vintage Lifestyle
21:22
Starting The Big Old 1935 Deutz Diesel. "OSHA left the chat"
780.1K views7 months ago
YouTubeYesterdays Machinery
16:11
Why Deutz F6L912 Was Banned: The Engine That Was Too Strong
356.3K views9 months ago
YouTubeAmerican Vintage Lifestyle
4:07
Engine Types and Styles Deutz Air Cooled
250.1K viewsFeb 12, 2015
YouTubeFanshawe Motive Power
45:42
Deutz Diesel Engine Restoration
47.6K viewsJan 16, 2024
YouTubeThe Awesome Skills
4:52
Deutz Engine Animation
8.9K viewsJun 10, 2021
YouTubeTRTP 72
0:27
💥 Worlds First!! 💥 Twin Turbo Air Cooled Engine
5.8K viewsJan 15, 2024
YouTubecombust components
23:13
Diesel ice cream maker churns nostalgia | Vintage diesel engines & engineering heritage
7.5K views7 months ago
YouTubeFUTEK HD
See more

Short videos

1:19
Ron Fits a DEUTZ V10 Into an M4 Sherman — What Could Go Wrong?
19.1K views3 weeks ago
YouTubeThe Australian Armour &
0:07
DEUTZ BF6M1013 diesel engine
2.1K views3 weeks ago
YouTubeMOMENTUM POWER
0:10
DEUTZ Compressor 12 volt starter testing
3.7K views1 month ago
YouTubeProTech Electrical Solutions
0:09
2026 Deutz-Fahr 4080E Review – Lohnt sich dieser 75 PS Traktor wirklich?
1.2K views1 week ago
YouTubeAuto Reviews 391
0:22
Exploring the Deutz Turbo 8006: Features and Benefits
18.7K views3 months ago
TikTokboening01
1:12
Deutz-Fahr Tractor Evolution (1927-2023) | The Legendary Air-Cooled Giants! ShiftEvo
242.6K views1 month ago
YouTubeShiftEvo
0:53
DEUTZ-F4L 1011 F
923 views1 month ago
YouTubeEngine technician
0:23
deutz fahr agrolux 55e 2026
1.2K views2 weeks ago
YouTubeUTalk india
0:50
Deutz fahr Splitter PTO shaft #deutzfahr #4wd #tamil #new
26.7K views2 weeks ago
YouTubeAgriculture INDIA
0:13
Deutz-Fahr Tractors Evolution 🚜 | Then vs Now (1980s–2026)
20.3K views1 month ago
YouTubeMZRT Bedbin
0:34
🔧 Power meets practicality on the Mantis Prime Mover.
821 views2 weeks ago
YouTubeEJ Equipment
1:45
🚜💪🏼 Diesel Power 2026 Deutz Fendt Farmer 105 S with Turbomatic #TractorTrac 🛠️ 🔥
2.9K views1 month ago
YouTubeHanseathanse
2:57
#deutz#dieselengine#engineering#industrialengines#machinery#mechanic#dieselpower#heavymachinery
1.1K views2 months ago
YouTubeOctane Nation
1:07
THRASH!! From inside the dual V8 Deutz engine car! 😎🔥 #GTWD #DieselPower #Breng -
1.1K views2 months ago
YouTubeTrainsbyM
0:26
NEW DEUTZ-fAHR agrolux 50hp 15+15 tractor unloading video #tractor #deutz
99.3K views1 month ago
YouTubeMohantractor's Life
0:44
how to timing the deutz engine, #mechanic
1.1K views4 months ago
YouTubeRD Mix Vlog
1:36
Fendt vs Deutz-Fahr (1930-2024)! Fendt Dieselross to 1050 Vario! ShiftEvo
123.8K views3 weeks ago
YouTubeShiftEvo
0:14
Deutz-Power mit über 4000 PS - 'Dschinni Evolution' Superstock Pulling Traktor
11.2K views3 weeks ago
YouTubeFischda
0:54
1972 Deutz D8006: Air-Cooled Legend Restored! 🚜💨#shorts
56.4K views3 months ago
YouTuberestore anything
0:39
Deutz Diagnose Kit for EMR2 EMR3 EMR4 | Fast Engine Diagnostics
151 views3 weeks ago
YouTubeOBD2TOOL

Shop deutz engine

Sponsored
About our ads
$33,774.14
Part 900-6035-30: Replacement Engine, Deutz Bf4l2011, 79Hp For 3200T | Bandit Industries
ModernEquipmentParts.com
$33,774.14
Part 900-6035-30: Replacement Engine, Deutz Bf4l2011, 79Hp For 3200T | Bandit Industries
ModernEquipmentParts.com
$10,868.00
D7E Engine Deutz 4 Engine Motor For Vplvo EC290 L04 2V C290 L04 2V D7D D6E D6D
eBay
Free shipping
$10,868.00
D7E Engine Deutz 4 Engine Motor For Vplvo EC290 L04 2V C290 L04 2V D7D D6E D6D
eBay
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6L Engine 53039880723
TurboTurbos
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6L Engine 53039880723
TurboTurbos
$10,926.80
JLG Part 1001251857 - ENGINE, DEUTZ LRC TD3.6L 100HP
Zuma Sales LLC Store PMAX
$10,926.80
JLG Part 1001251857 - ENGINE, DEUTZ LRC TD3.6L 100HP
Zuma Sales LLC Store PMAX
$1,195.00
NEW Borgwarner K27.2 Turbo Deutz Tractor Truck BF6L913 Diesel Engine 53279886409
TurboTurbos
$1,195.00
NEW Borgwarner K27.2 Turbo Deutz Tractor Truck BF6L913 Diesel Engine 53279886409
TurboTurbos
$10,646.00
Complete Deutz F4L 1011 F Engine, Genie S-60, S-65, JLG, 600S, 660SJ, Bobcat
eBay
$10,646.00
Complete Deutz F4L 1011 F Engine, Genie S-60, S-65, JLG, 600S, 660SJ, Bobcat
eBay
$795.00
S400 Turbo Deutz Industrial Gen Set BF6M1015CP COM2 Diesel Engine 319124 319192
TurboTurbos
$795.00
S400 Turbo Deutz Industrial Gen Set BF6M1015CP COM2 Diesel Engine 319124 319192
TurboTurbos
$24,310.00
JLG Part 1001148159XED - ENGINE, DEUTZ TD2.9
Zuma Sales LLC Store PMAX
$24,310.00
JLG Part 1001148159XED - ENGINE, DEUTZ TD2.9
Zuma Sales LLC Store PMAX
$13,453.02
Part 1001148076XED: JLG ENGINE, DEUTZ LRC TD3.6L 100HP
ModernEquipmentParts.com
$13,453.02
Part 1001148076XED: JLG ENGINE, DEUTZ LRC TD3.6L 100HP
ModernEquipmentParts.com
$2,900.00
Deutz D 2011 L 03 Air Cooled Diesel Engine 3 Cylinder
eBay
Free shipping
$2,900.00
Deutz D 2011 L 03 Air Cooled Diesel Engine 3 Cylinder
eBay
$10,250.00
New Deutz TCD3.6L4 Industrial Diesel Engine 95Kw @ 2200Rpm, 127Hp, Tier 4 Final
eBay
$10,250.00
New Deutz TCD3.6L4 Industrial Diesel Engine 95Kw @ 2200Rpm, 127Hp, Tier 4 Final
eBay
$15,262.22
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$15,262.22
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$9,995.00
New DEUTZ, F4L912 Engine Freight Included US48 Tag 70816
eBay
Free shipping
$9,995.00
New DEUTZ, F4L912 Engine Freight Included US48 Tag 70816
eBay
$4,895.00
Deutz TD2011 Engine Block
eBay
$4,895.00
Deutz TD2011 Engine Block
eBay
$3,090.00
Deutz 3 Cylinder Air Cooled Diesel Engine F3LW912W
eBay
$3,090.00
Deutz 3 Cylinder Air Cooled Diesel Engine F3LW912W
eBay
$450.95
New OEM Deutz Engine Kit 31013S1Z
eBay
Free shipping
$450.95
New OEM Deutz Engine Kit 31013S1Z
eBay
$11,900.00
Deutz F4L1011F Diesel Engine Family, YDZXL02.7018, 47HP, 2.73L, Engine Code: C35
eBay
$11,900.00
Deutz F4L1011F Diesel Engine Family, YDZXL02.7018, 47HP, 2.73L, Engine Code: C35
eBay
$4,250.00
Deutz F2L1011F Engine Exchange Or Rebuild Yours !!! READ DESCRIPTION !!!
eBay
Free shipping
$4,250.00
Deutz F2L1011F Engine Exchange Or Rebuild Yours !!! READ DESCRIPTION !!!
eBay

Shop deutz engine

Sponsored
About our ads
$7,268.88
Engine Assembly For Deutz Engine TD2.9 L4
Fridayparts.com
$7,268.88
Engine Assembly For Deutz Engine TD2.9 L4
Fridayparts.com
$20,520.00
Engine Assembly Air Cooled F2L912 2 Cylinder 4 Stroke For Deutz 912
eBay
Free shipping
$20,520.00
Engine Assembly Air Cooled F2L912 2 Cylinder 4 Stroke For Deutz 912
eBay
$616.00
NEW S100 Turbo Deutz BF3M2011 BF3L2011 2.33L Diesel Engine 04280664KZ 318195
TurboTurbos
$616.00
NEW S100 Turbo Deutz BF3M2011 BF3L2011 2.33L Diesel Engine 04280664KZ 318195
TurboTurbos
$8,189.99
53.7KW 2700Rpm/Min Engine Assembly For Deutz TD2011L041
Fridayparts.com
$8,189.99
53.7KW 2700Rpm/Min Engine Assembly For Deutz TD2011L041
Fridayparts.com
$11,900.00
NEW 2021 Deutz TCD3.6L4 Diesel Engine, Family MDZXL03.6060, 120HP, Tier 4Final
eBay
Free shipping
$11,900.00
NEW 2021 Deutz TCD3.6L4 Diesel Engine, Family MDZXL03.6060, 120HP, Tier 4Final
eBay
$23,091.99
74.4KW 2300Rpm/Min Engine Assembly For Deutz TCD3.6 L4
Fridayparts.com
$23,091.99
74.4KW 2300Rpm/Min Engine Assembly For Deutz TCD3.6 L4
Fridayparts.com
$16,600.00
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$16,600.00
For Deutz Td2011l04i Engine Motor Power 37-75Kw Rpm2400
eBay
$16,830.08
Engine Assembly For Deutz D2011L03I
Fridayparts.com
$16,830.08
Engine Assembly For Deutz D2011L03I
Fridayparts.com
$13,919.20
Engine Assembly For Deutz BF6M1013FC
Fridayparts.com
$13,919.20
Engine Assembly For Deutz BF6M1013FC
Fridayparts.com
$13,798.50
Multiquip Genuine Part D2011L02I Engine Deutz 29.9 HP MQ62TDD
SLE Equipment
$13,798.50
Multiquip Genuine Part D2011L02I Engine Deutz 29.9 HP MQ62TDD
SLE Equipment
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6 Diesel Engine 53039880725
TurboTurbos
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6 Diesel Engine 53039880725
TurboTurbos
$33,774.14
Part 900-6035-30: Replacement Engine, Deutz Bf4l2011, 79Hp For 3200T | Bandit Industries
ModernEquipmentParts.com
$33,774.14
Part 900-6035-30: Replacement Engine, Deutz Bf4l2011, 79Hp For 3200T | Bandit Industries
ModernEquipmentParts.com
$10,868.00
D7E Engine Deutz 4 Engine Motor For Vplvo EC290 L04 2V C290 L04 2V D7D D6E D6D
eBay
Free shipping
$10,868.00
D7E Engine Deutz 4 Engine Motor For Vplvo EC290 L04 2V C290 L04 2V D7D D6E D6D
eBay
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6L Engine 53039880723
TurboTurbos
$895.00
NEW OEM Borgwarner K03 Turbo Deutz Industrial TCD 3.6L Engine 53039880723
TurboTurbos
$10,926.80
JLG Part 1001251857 - ENGINE, DEUTZ LRC TD3.6L 100HP
Zuma Sales LLC Store PMAX
$10,926.80
JLG Part 1001251857 - ENGINE, DEUTZ LRC TD3.6L 100HP
Zuma Sales LLC Store PMAX
$1,195.00
NEW Borgwarner K27.2 Turbo Deutz Tractor Truck BF6L913 Diesel Engine 53279886409
TurboTurbos
$1,195.00
NEW Borgwarner K27.2 Turbo Deutz Tractor Truck BF6L913 Diesel Engine 53279886409
TurboTurbos
$10,646.00
Complete Deutz F4L 1011 F Engine, Genie S-60, S-65, JLG, 600S, 660SJ, Bobcat
eBay
$10,646.00
Complete Deutz F4L 1011 F Engine, Genie S-60, S-65, JLG, 600S, 660SJ, Bobcat
eBay
$795.00
S400 Turbo Deutz Industrial Gen Set BF6M1015CP COM2 Diesel Engine 319124 319192
TurboTurbos
$795.00
S400 Turbo Deutz Industrial Gen Set BF6M1015CP COM2 Diesel Engine 319124 319192
TurboTurbos