|    | LD451/452 Simplex Lock |   | Features:  Features Access Control: Mechanical pushbutton lock eliminates problems and costs associated with issuing, controlling, and collecting keys and cards No Battery: Fully mechanical lock eliminates the material and labor expense of battery replacement Locking Device: Tubular latch Number of Codes: Single access code—one easy to manage code for all users Programming: Lock is programmed via keypad once removed from door Handing: Pre-assembled for right hand door installations (easily changed in field) Key Override: Not available Operation Modes: Single credential—access Latch holdback (easily removed in field) Economical: A cost effective access control solution Mechanical Features Construction: Solid cast housings; cast knob and lever Numeric Keypad: Vandal resistant, metal push buttons Door Handing: Pre-assembled for right hand door installations (easily changed in field)| Backset: 2 3⁄4" (70 mm) backset, 2 3⁄8" (60 mm) backset Latch: 1⁄2" (13 mm) latch Minimum Stile 3 1⁄2" (89 mm)  |  |