We produce 4 main ranges of pressure control valves : Small in-line valves for mobile applications Sub-plate mounted industrial valves (CETOP 7, 8 and 10) Stacking (CETOP 3 and 5) - also x-port Mobile overcentre valves This photo shows a simple in-line pressure relief valve. This range of valves have dash-pot damping to reduce vibration and noise. This valve is available in various sizes with optional panel mounting and various control options - knob, screw or fixed.