The GZR U4 is a sturdy U-lock that protects your vehicle from thieves. The 16mm thick steel shackle is not easily broken, and the four-star ART security-rated lock will not open even in the hands of a clever thief. The U-lock is harder to cut than other locks due to its solid construction, and it can be conveniently attached to the bike frame using the included bracket.

Materials include PP, zinc alloy, PVC, and steel. The shackle thickness is 16 mm with an inside depth of 194 mm and an inside width of 104 mm. It comes with two keys and weighs 1600 g.

The ART Foundation is an organization that has created a five-level classification system for the theft prevention capability of bike locks.

1 star: minimum level protection
2 stars: basic for bicycles
3 stars: for mopeds
4 stars: for motorcycles in temporary parking
5 stars: for motorcycles in long-term storage

It's advisable to regularly lubricate the lock mechanism with a light oil to ensure smooth operation and prevent freezing.