Bodies are manufactured from high quality SG iron. Jaw tenons with hard and ground wear strips are fitted on chucks above 125mm. Component parts are manufactured from high quality alloy steel and are appropriately heat treated for optimum performance and durability. The hard inside and outside jaws supplied can also be used in the Super Precision and Griptru scroll chucks. Hard base and reversible jaws are available on request. Accuracy is to ISO 1089:9191 (E) class 11.