The Makita 20oz. Barrel Holder Set (1911T4-0) is for use with the 18V LXT® 29 oz. Caulk and Adhesive Gun (XGC01). The Barrel Holder is very versatile, allowing the 29 oz. Caulk and Adhesive Gun to hold a variety of cartridges, including cartridge style, sausage style, as well as bulk caulks and adhesives. This complete set includes all you need to utilize the three primary styles of containers. It is made of high quality materials for added durability.