The finest in antique screwdrivery, this screwdriver is based on an 1904 patent by William Ward, but with several modern improvements. You can view the original patent here: https://patents.google.com/patent/USD... Each screwdriver is made from 1144 steel, ~9in/22.8cm long, and weighs 0.44lb/200g. The square shaft is 3/8in/0.95cm thick. The blade is 0.5in/1.27cm wide and 1/8in/0.3cm thick. Blade is hardened to 52 HRC.