This automatic air grease gun gives you smooth, precise, continuous grease flow for professional results. The variable speed trigger delivers infinite flow control for everything from large bearings to tight grease fittings. The pump is engineered for easy priming and constant use. The pneumatic grease gun stops automatically when a grease fitting is stuck, blocked or broken. Balanced ergonomic design and a nonslip grip make this grease gun effortless to use in all positions and for extended periods of time.