VPS Impression Dispensing Gun 1:1 Ratio Type 25. Fits most 25ml cartridges. The Dispensing Gun 1:1 by 32Cart is used to extrude core materials from cartridges. It consists of a release lever and a plunger, which are coordinated simultaneously to load and remove the cartridge. The gun also consists of a trigger to dispense the material. Works with 1:1 cartridges. COMPARES TO: Clinicians Choice, Pentron, Vivadent VPS 1:1 Dispensing Gun.