TT Top of the line grease gun designed for heavy industrial applications solid aluminum grease gun head fitted with air bleeder and bulk loader valves 1.2 mm thick steel barrel with heavy duty follower spring, cnc machined head and rolled threads for fast and easy reloading unique lock lever mechanism: Allows user to easily lock plunger rod in any position multiple loading: Cartridge, suction fill and filler pump via the bulk loader variable stroke feature built-in for usage in confined spaces resists back pressure, especially useful in chain tightening of earth moving equipment.