In about 1898, the standards for threaded fasteners based on metric dimensions were developed using Sellers' basic thread geometry, but differ from the USS in that its pitch and dimensions are based on metric units.
The standards for threaded fasteners were developed using Sellers' basic thread geometry. This was in about 1898. These threaded fasteners were based on metric dimensions. The standards for threaded fasteners differ from the USS in that its pitch and dimensions are based on metric units. This was in about 1898. These threaded fasteners are based on metric dimensions.