These clamps hold workpieces on the ID or OD using machinable jaws (available separately). For OD clamping, the aluminum jaws can be machined to custom fit the workpiece. For ID clamping, the workpiece is placed over ID jaws, which expand outward using a tapered pin (available separately). The part repeatability is +/- 0.03 mm, and the jaw locating repeatability of +/-0.02 mm. The clamping stroke of each jaw is .3 mm for both OD and ID clamping. The body is made from 1045 steel with an electroless nickel plated finish. The pull cylinder is made from 4115 steel, carburized-hardened with a black oxide finish. The cam cylinder is made from 4135 steel, quenched and tempered, with a black oxide finish. Jaws and tapered pins must be purchased separately. Note: Do NOT actuate the clamp without a workpiece to avoid damaging the clamp and jaws.Compatible with the CP126 for OD (outer diameter) perimeter holding or the CP127 for ID (inner diameter) internal holding, these machinable jaws offer exceptional versatility for even the most complex workpieces. Fully customizable, they can be precision-machined to your exact specifications — delivering a secure, reliable grip whether you're clamping from the inside out or the outside in.