Combination bicycle locks

Combination lock

— built-in locks (see the relevant paragraph), locked and opened not with a key, but with a digital code. Having memorized the code, you don't have to worry about it being lost or stolen; at the same time, if desired, it can be communicated to another person (for example, a relative), giving him access to the lock. At the same time, care must be taken to ensure that the cypher is not spied on or overheard. Also, note that the number of digits directly affects the reliability of a combination lock — the more there are, the more difficult it is to open the lock by brute force combinations.