Locking bolts

Secret

— “Secrets” are bolts and nuts that have a non-standard head shape, which does not allow removing such a part with a traditional tool like a hex wrench or pliers. On the sides, the head or “secret” nut is usually smooth, and the grip to the key provides a special-shaped slot in the end. Moreover, the shape of this slot can be different: in the form of several petals (sometimes also of an unequal shape), asterisks (there are different options for the number and shape of “rays”), etc.

This design provides additional protection against theft of wheels: to work with a lock, you need a special key, moreover, suitable for this type of fastener. Of course, even the most cunning secret does not give a 100% guarantee against “shoeing”, but it can definitely “complicate life” for a robber.