Single- or double-acting power clamping swing cylinders for workholding are hydraulically-activated and available in top or bottom flange styles. They can be manifold-mounted, with #2 SAE ports, or plumbed through two #4 SAE ports. Three sizes offer clamping capacities from 1100 to 5000 lb. Clamps' piston rotates 90° clockwise; 90° counterclockwise rotation or no rotation is optional. They can be used via a through hole bottom mount or top plate mount. Non-threaded bodies simplify mounting.