Note: Maximum flow rates are based on an 8 ft/sec plumbing velocity. Use only 500XL3BPK or 500XL3DUBP for low-flow bypass applications. The 500XL3 supports up to 400 PSI inlet, 15-75 PSI (Standard) or 60-125 PSI (High Range) outlet, and a maximum 3:1 pressure reduction ratio per valve. Contact your Wilkins representative for applications outside these limits.