Image 400-Series Hammer Union Markets Energy / Oil & Gas Jump to Section Product Options Related Products Product Options Part Number Size Material HU400200 2" Forged Steel HU400300 3" Forged Steel HU400400 4" Forged Steel Related Products Image Dixon Complete Assembly Frac Fitting Image EZ Boss-Lock Cam & Groove Type C Coupler x Hose Shank Image Forged Steel Gate Valve Image 206-Series Hammer Union Image 602-Series Hammer Union Image King Combination Nipple NPT Threaded End No Knurl