Kaba Simplex 91026D Auxiliary Lock with Thumbturn; Key Override; 1" Deadbolt for 1-3/4" to 2-1/8" DoKaba Simplex 91026D Auxiliary Lock with Thumbturn; Key Override; 1" Deadbolt for 1 3 4" to 2 1 8" Door Satin Chrome Finish Mechanical Pushbutton Lock Eliminates Problems and Costs Associated with Issuing, Controlling and Collecting Keys and Cards Provides Fully Mechanical Access Control at All Times While Allowing Free Egress At All Times By Interior Thumbturn Deadbolt Models Must Be Manually Relocked; Spring Latch Models Automatically Relock Each