Closes an unused manifold port The cap can be fitted to an unused 3/4″ circuit outlet on a compatible 413 Series manifold, allowing the remaining manifold circuits to be connected and commissioned as required. Integral sealing washer A rubber washer is built into the cap, so a separate fibre washer is not required. Check that the sealing face and washer are clean and undamaged before fitting, then test the completed connection for leaks.