Seatylock Mason Lightweight Sold Secure Diamond Bike U Lock
- 19/20 Diamond Sold Secure rating
- 1.07 kg listed weight
- 5.5 x 1.37 x 9.6 inches
- Triangular crossbars, double deadbolt
- 3 keys plus key duplication card
- 3 year manufacturer warranty
Last refreshed Oct 3, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A lightweight U-lock with a Sold Secure Diamond rating for bikes, e-bikes, scooters and motorcycles. The mounting bracket is sold separately.
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ASIN: B0D3BFMBMWModel: UM180-ONCategory: U-Locks
Overview
Locking a bike, scooter or motorcycle to a fixed rack is the job of this U-lock. Patented triangular crossbars with a double deadbolt secure the shackle, and hardened steel lies beneath a polymer cover.
The headline is a high security rating combined with low weight for its size. No codes or chain are needed, and the cover is built to resist scratches and weather. A mounting bracket for carrying the lock is not part of the product.
Who it's for
Commuters and urban cyclists locking up in public spaces are the target. It also covers scooters and motorcycles.
Pros and cons
- High Sold Secure rating
- Lightweight for its security level
- Anti-drill and cut resistant features
- Three keys included
- Mounting bracket sold separately
- Shackle opening size not stated
Performance notes
A hardened steel shackle resists cutting and drilling, while the triangular crossbars and double deadbolt hold it closed. The polymer cover protects the steel from weather, and a keyhole shutter blocks dust.
Specifications
| Brand | Seatylock |
|---|---|
| Model | UM180-ON |
| Dimensions & fit | |
| Inside size | 5.5 x 1.37 x 9.6 inches |
| Weight | 1.07 kg |
| Construction & materials | |
| Material Type | Hardened steel with nylon 6 and glass fiber cover |
| Color | Black Diamond |
| Included components | |
| Included Components | Lock, 3 automotive standard keys, key duplication card |
| Warranty & support | |
| Warranty | 3 year manufacturer defects warranty |
| Other details | |
| Lock Type | Triangular crossbars with double deadbolt |
| Shape | Oval |
| Maker security rating | 19/20 Diamond Sold Secure |
| Use | Bicycles, e-bikes, mountain and city bikes, scooters, motorcycles |
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Frequently asked questions
Does the Seatylock Mason come with a mounting bracket?
No. The description says the mounting bracket to hold the lock is not part of the product and is sold separately.
Can I use the Seatylock Mason on an e-bike or scooter?
Yes. Recommended uses include electric bikes, scooters and motorcycle security.
How many keys come with the Seatylock Mason?
Three automotive standard keys and a key duplication card.