The locks found at department stores, local home improvement retail stores or even hardware stores may be labeled as high security, but real high security locks aren’t typically sold in those places. If the lock you have doesn’t have a rating or if it has a Grade of 1, 2 or 3, it is not authentic. A UL 437 rating is the only indication that a lock is a true high security lock, and these are only available at a lock shop or from a locksmith. If your lock has come from any other place, it’s a good idea to have a professional locksmith look at it.