A huge bolt of laminated stainless steel, nearly three inches long, activated by an uncomplicated pivot mechanism, has made this basic MS Deadlock the standard of the narrow stile door industry. The length of this bolt provides maximum security for a single leaf door, even a very tall and flexible one or an installation where the gap between door and jamb is greater than it should be. 360 degree turn of key or thumbturn throws or retracts the counterbalanced bolt. Key can be removed only when bolt is in a positively locked or unlocked position. Lock accepts any standard 1-5/32" diameter mortise cylinder or thumbturn from either or both sides. Cylinder must have MS dimensioned cam. Latch bolt is 5/8" X 1-3/8" X 2-7/8" with 1-3/8" throw. Eight ply laminated stainless steel. Center ply has Alumina- Ceramic core to defeat any hacksaw attack, including rod-type “super” hacksaws. Cylinder Backset 7/8", 31/32", 1-1/8" or 1-1/2" only. Case Steel with corrosion-resistant plating. 1" X 6" X depth (depth varies with backset)