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 in , 5/16 in , 3/8 in , 1/2 in , 9/16 in and Ceiltile from light to heavy duty work. Used by building contractors, home do-it-yourselfers, and speciality trade applicators.