Unlike conventional spring plungers, the Jergens Solid Drive Plunger is one integral piece of steel: hex drive, plunger, and body. No set screw to separate from plunger body, no lost springs to retrieve, no need for easy-out tools. Best of all, when adjusting Solid Drive, you can be sure the spring plunger is turning and not just a set screw.Picture for category Steel Spring PlungersFeatures and Benefits:Single unit constructionNo set screw to separate from plunger bodyNo need for easy-out toolsBetter reliabilitySteel tips are a hardened steelClose tolerance between tip and bodyMaterials:Material: Body, Low Carbon SteelTip: SteelSpring: 17-7 PH Stainless SteelThread: 2A-UNCFinish: None or Black OxideAvailable in FixturePro Design Software and Fixture Pro Plus for 3D Solid Models on CD