CMP Return Wall Fitting [1-1/2" Slip x 2" Spigot, w/ Eyeball] [White] (25523-700-000) grasslin A probe cap is useful

A probe cap is useful because it helps cover and protect the probe opening

Designed for compatible outdoor deck installations

An O-ring like this is useful because it helps keep the inline union leak-resistant while preserving the serviceable nature of the connection for future maintenance

It is a useful part when equipment or plumbing layouts require a secure change from rigid threaded connection to flexible hose

That helps avoid replacing the full assembly unnecessarily

CMP Return Wall Fitting [1-1/2" Slip x 2" Spigot, w/ Eyeball] [White] (25523-700-000) grasslin A probe cap is usefulThe CMP Return Wall Fitting [1 1 2" Slip x 2" Spigot, w Eyeball] [White] is a practical replacement return fitting for service work where matching the original configuration matters more than making a broad, generic substitution. It is intended for return, inlet, or outlet plumbing locations where a secure fit and correct face style help direct water flow and finish the pool wall opening cleanly. Key identifying details from the listing include 1 1 2"