🔐 Lock in your peace of mind — because your bike deserves the best.
The Master Lock 8170D is a heavy-duty U-lock designed for serious bike security. Featuring a 6-1/8 inch wide hardened steel body and an 8-inch double-locking shackle, it offers superior resistance to cutting and prying. Lightweight at just under 2 pounds and equipped with a carrier bracket, it balances portability with impenetrable protection. Ideal for urban and suburban cyclists, this lock ensures your bike stays exactly where you left it.
| Brand | Master Lock |
| Special Feature | Heavy Duty |
| Lock Type | Key Lock |
| Item dimensions L x W x H | 9.8 x 7.33 x 1.33 inches |
| Material | Alloy Steel, Rubber |
| Recommended Uses For Product | Bike |
| Style | Lock |
| Color | Black |
| Number of Pieces | 1 |
| Finish Type | Vinyl Coating |
| Included Components | U-lock bike lock, two keys, and a carrier bracket |
| Controller Type | Hand Control |
| Shape | U Shape |
| Item Weight | 2 Pounds |
| Control Method | Touch |
| UPC | 071649222771 |
| Model Name | 8170D |
| Global Trade Identification Number | 00071649222771 |
| Manufacturer | Master Lock |
| Part Number | 8170D |
| Item Weight | 1.96 pounds |
| Product Dimensions | 9.8 x 7.33 x 1.33 inches |
| Country of Origin | China |
| Item model number | 8170D |
| Is Discontinued By Manufacturer | No |
| Size | 6-1/8 inch U-Lock |
| Finish | Vinyl Coating |
| Item Package Quantity | 1 |
| Special Features | Heavy Duty |
| Batteries Included? | No |
| Batteries Required? | No |
| Warranty Description | Limited Lifetime Warranty |
H**S
Nice lock
Fits my needs. Seems strong. Big enough to wrap around the bike and the rack. Cable is nice for fork/front tire. Key turns smooth every time.
D**T
Nice and Sturdy.
I can even lock 2 electric scooters with it at the same time.
S**A
Ideal for those who make a quick trip
Lock is functional, the length was just right for my 35mph e-scooter. The thickness was not that much hardly but it does the job. It comes with a two set of keys.Pros: Great for short trips, ideal for low crime areas but better safe than sorry type of person, easy to lock, affordable, sleek look.Cons: Not for long trips.
S**O
Does the job!
Adependable choice for keeping your bike secure. The locking mechanism is straightforward and works smoothly, giving me confidence that my bike is protected. The steel cable feels durable and resistant to cutting, providing a solid deterrent against theft. The length is just right for locking my bike to various fixtures, and the included key adds convenience over combination locks.I’m giving it 4 stars because the key mechanism, while reliable, feels slightly less sturdy than expected. I also noticed that the lock can be a bit finicky to open in cold weather, which might be an issue for some users. Despite these minor issues, this lock provides excellent value and peace of mind for daily bike security.
Z**K
Haven’t had a bike stolen since using this lock
It’s a solid, thick bicycle lock, but not heavy. I’ve watched videos online proving these can be cut with bolt cutters, but it doesn’t LOOK like it can be cut, so any thief takes a quick look and leaves my bike alone. That’s my theory, anyway. Also, I always lock my bicycle in visible places where the thief messing with my bike is gonna have people watching him.
B**N
Good would buy again…
Good quality would buy again. A must with quick release wheels
H**A
Works great!
Incredible! Keeps my bike nice and secure.
T**S
Lock rusted after 1 year at college
Bought this for our son off at college in Aug 2024. Bike locked outside daily. In May, had difficulty unlocking bike as inner mechanism rusted from outside use. Almost couldn’t turn key to unlock! Replacing lock for this next year…I don’t want to spend too much on a lock as the bike is over 25 years old…but still!
Trustpilot
3 weeks ago
1 month ago
