Padlocking Wing Knob provides the ability to lock a cabinet, providing extra security while maintaining a higher UL rating. When installed it cannot be rotated and the cabinet is secured. The maximum padlock diameter is .31 (8mm). This Wing Knob should be used with an existing cam for installation; a cam is not included with wing knob. The Wing Knob maintains the cabinet rating Type 3R, 4, 4X, 12.