Overview Reviews Product Description 31047 Hydraulic Union for Challenger lift. 9/16" O-ring to 3/8" compression. We are an authorized Challenger Distributor. Genuine Challenger Parts! Product Videos Custom Field Product Reviews Write a Review Write a Review × Challenger 31047 Challenger Hydraulic Union Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *