World's Lightest Sold Secure Diamond U-Lock!
Unique triangular crossbar profile for best strength/weight ratio. Double deadbolt locking mechanism for protection against twist attacks. *Mounting Bracket sold separately.
Hear what our customer has to say about his Mason 140
We bought the smallest Mason for our 11-year-old son to lock his bike at school. It is compact enough to carry in his backpack and is easy to lock. Previous lock used had problems with the key breaking and wearing out. We are not afraid with the Mason for this to happen. The mechanism is foolproof and with 3 keys, you cannot get wrong.
The Mason is a high quality D-lock that protects my bikes and seems better made than my On Guard locks. I like the feature that it holds itself together after being unlocked until you gently pull it apart.
Purchased the U-lock for use on Segway Ninebot E45 scooter and it works great for locking around either the stem/folding mechanism.
Tried out some of the local bike parking spots over the weekend without issue.
Key highlights of the design are being lower weight compared to many competing locks and extra level of security from the dual shackle locking design.
The automatic lock cover feature is pretty slick and I imagine will add to long term reliability of the U-lock.
Fulfilled my expectations. Also, very helpful customer service.
Lightweight but Gold level strength. Winning combo!
I purposely wanted a lock with small inner dimensions to minimize air space inside the lock and deter against prying attacks. This lock is exactly what I was looking for and is big enough to fit around my bike frame and bike racks/parking meters/posts in San Francisco while leaving a minimal amount of air space inside the lock. Haven't had the lock tested yet luckily but it seems to be made of high quality materials with good craftmanship. Also extremely light for a gold-rated lock. I did a fair amount of research on bike locks after having my last bike stolen using a pry attack against my u-lock and settled on the seatylock plus hexlox for my wheels.
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