I bought one of these macguard prop locks , reason staying at hotels and yes my buddy had his stolen ,not hard to do but gone in morning stainless which cost a good buck , well anyway they give you a black cap that fits over the lock unit to cover it up and for some reason and it does snap on after a while it's gone so I call and they send me one and couple times out gone , so is there a special way to put these on or don't even worry about having it on . thanks for any imfo