Night lock principle: the use of multiple different height of cylindrical parts (called lock spring, marbles or beads), lock the lock. When put in the right key, the lock spring is pushed to the same height, lock was let go. The essence of the false Ye Piansuo core or billiard structure, it is the key to the shape of leaf tissue structure, its internal lock core or marbles. Generic Ye Piansuo are very thin, the bead diameter is less than 2 mm.

   Ye Piansuo principle: the use of different bit keys, lock it is aligned to rotate different blade, so as to realize the lock core rotate open a lock, blade arrangement changes more than one hundred million times, regional mutual opening rate is close to zero.