Shop › 8mm Barbed Nipple 8mm Barbed Nipple $5.18 8mm Barbed Nipple to suit 5/8 nut. 8mm Barbed Nipple to suit 5/8 nut. Add To Cart Added! You Might Also Like 5/8 UNF Nut R/H 9/16 To 5/8 UNF 1/2" Nut & Nipple RH 1/2" Nut & Nipple LH 6mm Barbed Nipple