The Secoh Pressure Relief Valve is suitable for all Secoh Blowers, there is two different sizes available. This one is suitable for all Secoh JDK blowers between 150 and 500. 

The pressure relief valve can help prolong the lifespan of your air blower as if there is a build up of pressure the valve will release the excess air before it can cause lasting damage to the internal workings of the blower.

Best used alongside the Secoh Back Pressure Gauge - BP1