https://www.messplay.com/products/control-valves-regulators/straval-bps05-300-flg-stainless-steel-300-flange-back-pressure-bypass-valve/
StraVal BPS05-300-FLG Stainless Steel 300# Flange Back Pressure Bypass Valve – Messplay Machinery...
Use this regulating valve for back pressure control applications such as maintaining constant pump discharge pressures, bypassing excessive pressures from...
stainless steelflange backbypass valveflgpressure