Pneuflex's model of SPOC 06-03 is hex socket head male connector stainless steel push in fittings with 6mm O.D connector and R, PT, BSPT 3/8 male thread, round shaped body with internal hexagon, designed to connect pneumatic tubing of 6mm diameter to R, PT, BSPT 3/8 female thread in where the installation space is limited.