Machine Screw Jacks is a type of Screw Jack operates at full capacity in tension or compression used for heavy duty, self-locking, precision positioning. Screw jacks are made of Cold Drawn Steel (CDS) available in rotating, keyed screw and KFTN configurations. Translating screw is in upright or inverted configuration, available in WJ and DWJ Models. Visit Joyce Dayton at First E Source for more details.