Pentair .75" x 7/8" Hex Bushing

The Pentair $.75"$ Hex $\times$ $7/8"$ Threaded Bushing (part number 070548, 70548, or 070548Z) is a specialized internal pressure-relief plumbing fitting engineered exclusively for high-capacity pool and spa Diatomaceous Earth (D.E.) and cartridge filtration networks. This genuine original equipment manufacturer (OEM) replacement component is standard structural hardware designed for the integrated air relief valve assemblies of legacy Pentair SM & SMBW 2000-Series vertical grid D.E. filters, as well as classic cartridge filter models like the CFW, CF100, and CP150 lines.

Machined from heavy-walled, commercial-grade solid brass or heavy-duty engineering polymers, this dual-dimensioned bushing is styled with a distinct 3/4-inch hex-flanged head that transitions into a rugged 7/8-inch threaded shank profile. Its primary operational role is to anchor the high-flow air relief components directly into the upper dome port of the pressurized filter tank chassis. When paired with an elastomeric lid gasket and tight-sealing hex nut, the bushing forms an unyielding mechanical connection that safely isolates air-purging mechanisms under continuous system operating pressures up to 50 PSI.

By providing a precise threaded gateway for the manual or automatic air bleed systems, it allows trapped gas pockets to be cleanly exhausted from the filter dome. This vital stabilization prevents localized water-hammer pressure spikes and ensures uniform hydraulic fluid distribution across the internal filtration grids. Built to remain permanently exposed to a highly volatile, chemically active chemistry profile, its corrosion-resistant metal matrix completely resists advanced oxidation, thread-galling, and material degradation from constant contact with high-strength pool sanitizers like liquid chlorine, bromine, and seasonal maintenance acid washes. Due to its compact, solid-profile layout, this replacement hex bushing carries a nominal product and net shipping weight of approximately 0.10 to 0.15 pounds (about 1.6 to 2.4 ounces).