SPF® Anvil Steel Pipe Nipples Standard Welded Steel Pipe Nipples Material Specifications Dimensional: ASTM A733 Material: ASTM A53 Type F or Type E Galvanizing: Hot Dip Galvanizing* Threading: **NPT per ASME B 1.20.1 *Galvanized nipples are manufactured from pipe coated on the inside and outside by hot dip process