Whitworth Screw stock taps

Whitworth Screw stock taps, dies, wrenches, die wrench and spanner: 5 sets of taps (4 in each set), 5 sets of dies (3 in each), 3 wrenches for taps, a die wrench and 1 spanner.

One of Whitworth’s important legacies was an agreed national specification of screw-thread shape and pitch, related to the diameter of the bolt; before his work, each machine shop used a special thread of its own. Starting in 1841, his standard became generally accepted and by 1860 it had become a British Standards Institute specification remaining in general use until well into the 1960s.