3a all ends thread class 2.750" overall length fluid end is a bulkhead fitting anodize body surface treated male coupling half unjf all ends thread series
4 2nd end bolt hole quantity boss 2.13 in. cen to first end inside curve of elbow, 1.00 in. od, 0.5625-18unjf-3b per MS33649-6; boss 1.75 in. cen to second end outside curve, 0.80 in. od, 0.4375-20unjf-3b per MS33649-4