All steel construction; high carbon hardened steel working parts. Visual refill window. Patented jam-proof mechanism. Easy double leverage operation. Loads (85) Arrow No. T-50 staples only of .050 wire in 6 sizes; 1/4", 5/16", 3/8", 1/2", 9/16" and Ceiltile from light to heavy duty work. Used by building contractors, home do-it-yourselfers, and speciality trade applicators.