The 3M™ Socket, W-3224-2 is used on the 3M™ Supplied Air Hose, W-3020, Low Pressure. It is a 3/8 in (0.94 cm) FPT brass fitting.Delve into 3M Products and experience the wide variety of products and replacement parts offered with powered air purifying respirators (PAPR). In addition to powered systems, 3M also offers supplied air respirators (SAR) using air from an air tank or a different external source.