Red Devil Red Devil Caulking Gun, Half-Barrel, 1/10 gal, 630-3985 Red Devil half-barrel caulk gun with smooth rod and quick-release mechanism is suitable for light-to-medium applications of glazing, sealing or caulking. Holds most standard cartridges and has a thrust ratio 7:1. MSRP: $5.49 Was: $3.50 Add to Cart Compare Quick view