The M12 series cartridge caulk guns features a 12:1 thrust ratio, it is best used with standard materials like latex, silicone, polyurethane and others for fast action. Comes with two standard sizes fits 10 oz. cartridge (M12S) or a 1-quart cartridge (M12L). The M12 series caulk guns features an ergonomic grip, a curved hook for hanging on racks or ladders, a built-in puncture pin and a thumb-operated pressure release lever.