HW9505-2 – Engine Turned Stainless Steel Stepped Lid Insert – The Stepped Lid Insert is the perfect addition to the Billet X Master Cylinder if you have the Stepped Lid Option. Simply remove the adhesive tape and place it in the center of the lid. Water Jet cut from 0.030″ thick Engine Turned Stainless Steel, it’s that last little thing needed to make your engine compartment what you dream of it being.