Hot Tub Filter Cartridge 7CH-975 Dimension 1 Top Load w/SAE (70522) union Its wet end measures 6-1/2"

Its wet end measures 6-1/2" in diameter for higher head pressure

Sundance spas and many others

If you are replacing an older Ultra jet hot tub pump it is important to reference the high amps(OLD) instead of the HP

as per label

Sloan 2 LED Light Extension

Hot Tub Filter Cartridge 7CH-975 Dimension 1 Top Load w/SAE (70522) union Its wet end measures 6-1/2"ProAqua Filter Cartridges 7CH THREADED SERIES 7CH 975 Fits Dimension One #1561 12 Diameter: 7 ; length: 10 1 2 Top end cap: semi circular handle, 0" inner diameter; bottom end cap: 1 1 2" sae thread, 0" inner diameter Pleat count: 216; filter media: 3 oz reemay 2033; filter area: 75 sq. ft.