UNIVERSAL SIZE for most lamp - Fit a normal lamp switch/knob,threaded for a common table lamp socket. BRASS MATERIAL: standard switch knobs - Solid hole threads,never be stripped. Tighten up enough to operate the switch.BRASS raw material is rustproof and has long lifespan. APPLICATION - Great looking to upgrade the old plastic type on lamps; Replace stripped out knobs; Repair a lamp switch that missing lamp knobs;Repair a favorite older lamp that the little knob broke;Inexpensive fix for broken twist switch on table lamp. EASY TO USE - Twisted on easily,the lamp is as good as new. Just screwed it on, lamp can be turned on and off easily and smoothly., Manufacturer: CTRLZS