Pentair Triton II Side Mount FilterFiberglass Sand Filter Without Valves Triton II Side Mount Filters are the original and still the industry standard. Our unique process creates a one piece, fiberglass reinforced tank with UV resistant surface finish for years of unequaled strength and durability. This unique method locks in fiberglass, preventing fibers from "blooming" under harsh conditions. Heavy duty closure provides easy inspection Easy to read pressure gauge with air relief