PERKO 1/2 in. and 3/4 in. Perko Strainer Cork Gasket Kit 0493DP599M Replacement cork gasket set for #4 & #5 size Perko 0493 series 1/2 in. & 3/4 in. NPT intake water strainers. Perko cork strainer gasket kit For Perko 0493004PLB and 0493005PLB intake water strainers Kit includes (1) cork cover gasket and (2) cork cylinder gaskets For older model Perko strainers with cork gaskets – will not work in place of rubber gaskets