B19WX-R300 Dixon Valve 316L Stainless Steel Sanitary Tube OD Weld x Schedule 10S Weld Pipe Size Adapter - 3" Pipe SizeFeatures: 3A sanitary finish ID and OD Notes: Please note in sizes 1 2" through 12" pipe is known by its nominal inside diameter, which differs from its actual inside diameter. To distinguish pipe sizes from actual measured diameters as used for tube, the terms iron pipe size (IPS) or nominal pipe size (NPS) are usually used. For all pipe sizes, the outside diameter (OD) remains constant; the variations in wall thickness affect the inside diameter