UNLOADER (VB7) @ 3600PSI Pacific Bay Equipment Sale! from $106.00 Qty. Add to Cart This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Fits GP/Interpump 63 Series, CAT 4SF pumps as well as many other pumps requiring up to 8 GPM - 3650 PSI max pressure. PSI Max: 3650 Temperature: 195°F Weight: 19.7 oz. Without Knob, 3/8 MPT Inlet, 3/8 FPT Outlet & Bypass