Abstract: A locking device which includes a casing, a U-shackle, two locking plates mounted in the casing to lock the U-shackle in the casing, a lock cylinder driven by a card to release the locking plates from the U-shackle, wherein the lock cylinder includes a mounting shell mounted in the casing, a tumbler holder mounted within the mounting shell to hold a set of tumblers, a set of springs, and a set of steel balls, the steel balls being displaced to release the tumblers from the mounting shell for permitting the tumbler holder to be lifted to unlock the locking plates when the card is inserted through a card slot on the casing into a bottom slot on the mounting shell and a bottom slot on the tumbler holder.

Abstract: A supporting bracket includes a bracket body which defines a tube receiving portion and lock receiving portion. The tube receiving portion includes a split socket having a bush therein. The socket further includes a split threaded extension which receives a locking knob to tighten the split socket. An adaptor and a biasing block is further received by the locking block. When the locking knob is screwed in, the adaptor and biasing block are moved in to press against the bush. Accordingly, the supporting bracket can be firmly attached to the tube with different diameter of the bicycle. The lock can be readily held by the lock receiving portion when the lock is not in use.