The 3101 08 13 is a G1/4 straight adaptor male Stud Fitting with nickel-plated brass body, NBR O-rings, stainless steel gripping ring and hexagonal BSPP thread. In line connection of tubing to a threaded port. External tightening with a flat spanner or Allen key, internal adjustment with an Allen key. Solid construction, compact, aesthetic and unobtrusive for better connection.