Tell Manufacturing CL100004 SV Series Privacy Lockset – (KC2376). Heavy-duty commercial privacy ball knob. Satin stainless steel (US32D). Performance: Complies with ANSI A156.2, Series 4000, Grade 2, (400,000 cycles). UL listed for 3 hour fire door. Door range: 1-3/8″ to 1-3/4″. Backset: 2-3/4″ standard. Strike: T strike (1-1/8″ x 2-3/4″) standard. Cylindrical, steel-coated with zinc dichromate (corrosion resistance). Latch bolt operated by knob from either side. Outside knob locked by push-button on inside. Unlocked by emergency release on outside or rotating inside knob or closing door.