Tell Light-Duty Commercial Entry Ball Knob KT2181 . Light-duty commercial entry 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. Keying 6 pin SCC keyway with 2 nickel keys per lock. Door range 1-3/8 to 1-3/4 . Backset Adjustable 2-3/8 to 2-3/4 standard. Strike T strike 1-1/8 x 2-3/4 standard. Tubular construction. Deadlocking latch bolt operated by knob from either side except when outside knob is locked by push-button on interior. When exterior knob is locked, key in exterior knob or operating knob from interior unlocks push-button and retracts latchbolt. Closing door does not release push-button. Finish Satin Stainless Steel, Backset 2-3/8 In. or 2-3/4 In., Latch Adjustable Latch, Security Level Grade 2, Exterior Access Key, Interior Action Push Button, Pkg Qty 1, Package Type Clamshell