Brass, Plymouth Knob, Entrance Lock, Unlocked By Key From Outside When Outer Knob Is Locked By Turn Button On Inside, Inside Knob Always Unlocked, Dual Backset Latches, Fits Either 2-3/8" Or 2-3/4" Backset, 1-3/8" To 1-3/4" Door Range, 2 Keys, Ansi A156.2, 1996. Grade 2, Ulf Listed For 3 Hour Fire Door, Box Pack.