Built for needs around the shop, this pistol type grease gun is trigger operated. To ensure constant flow, a rubber plunger pushes all the grease in the barrel forward under a steady pressure. This product uses a standard 14 oz. cartridge or can be loaded with bulk grease. Equipped with air vent valve filler plug. Delivers 1200 to 3600 PSI when supplied 30 to 90 PSI from compressor. Minimal assembly required to attach the nozzle.