- All Spares accessories like Dowly Seals, Sealing Copper Washers, Ferrules are available. Also, Sump Strainers for suction filtering in pipe sizes 3/8" to 4" for 400 GPM available. Gauge Snubbers in 1/4, 3/8 & 1/2 connections are available ex-stock. Also Ball Valves, Quick Release Couplings, Rotary Joints, Cartridges are offered from Standard Product range.