Fail Safe/Fail Secure, Complete 12/24VDC Electric Strike, Surface Mounted, 1/2 Thickness, Latchbolt Monitor, Satin Stainless Steel". The 9400 ships with a 1/8 spacer plate to accommodate varying door gaps. The 9400 exceeds Grade-1 standards for strength and performance. It is field selectable for fail secure and fail safe operation, and for 12 or 24VDC. The 9400 features a smooth cover to conceal the mounting screws and provide a sleek surface for superior looks."