Becker VT 4.8 vacuum pumps come with a G 3/8" BSPP inlet thread. This thread size is primarily used in Europe and Great Britain. This adapter converts "G" BSPP thead to a KF-16 flange more commonly used in the universal world wide vacuum market.

BSPP = British Standard Pipe Parallel (straight thread) and is often noted G, for example, G(1/2).

BSPT = British Standard Pipe Taper (tapered threads).