A sturdy caulk gun for applying caulks, sealants, adhesives, glazing, and other cartridge goods. 1/10 gallon, heavy-duty uni-rail design with hex piston rod and quick-release lever. Fits all standard cartridges. Suitable for light to medium-duty applications. 10:1 Thrust Ratio Heavy duty. Unirail Construction Hex Piston Rod Push Release Lever.