Nptf 3 8 July 8, 2019 16 32 64 128 Npt 3 8 Npt 3 8 tap Npt 3 8 размеры Npt 3 8 elbow Npt 3 8 thread pitch Npt 3 8 barb Npt 3 8 18 Npt 3 8 x 18 Npt 3 8 to mm Nptf 3 8 dimensions Npt 3 8 drill size Npt 3 8 tap drill size Npt 3 8 vs g3 8 Npt 3 8 fitting