GearWrench 416D Ramo-Matic Zerk Fitting Tool GearWrench 416D Ramo-Matic Zerk Fitting Tool fits straight and angled zerk-type fittings, clears grease fittings of hardened materials, clean and maintain dirty grease fittings, the force of the oil or grease clears away dirt and grime in and around the fitting, fill with oil or grease and hold against zerk fitting; strike with hammer to clear away debris.