100% brand new and high quality Open the top of the dispenser and then pull the rack to reach the maximum. After fixing the mixing tips on cartridge, put into impression material cartridge, and lock it by the dispenser. Promote the trigger to make the impression material come out smoothly from the cartidge After using, put the rack back to the original location. Remove the cartridge, then to repeat the above operation. --Suggested Use Materials: Suggested Use Materials: Epoxies, Acrylics, Silicones, Polyesters. Epoxy Acrylates, Hybrids, Urethanes. Polysulfides, foams, Polymers, polyureas.Shadental