Pneumatic Shaft-Locking Clamps are automated quick locks with air for machine changeover. They provide secure clamping of sliding shaft and spindle after position adjustment of parts and units in the machinery. Spring clamping occurs when air is removed, and unclamping when air is provided. Spring clamping and pneumatic unclamping mechanism prevents the decrease of clamping force by air leakage. The body is made from 5052A aluminum alloy with a sandblasted finish. The O-ring is made from nitrile rubber.