The Unicel 7CH-975 is a top-load spa filter cartridge delivering 52 square feet of filtration across 216 pleats of Reemay® 2033 polyester media. Built to meet or exceed OEM specifications, it’s the replacement cartridge for Dimension One Spas, taking the place of OEM part 1561-12.
Filtration is the quiet backbone of clean spa water. Every soak leaves behind body oils, lotions, hair, and fine debris, and the cartridge is what removes all of it before it clouds the water, feeds bacteria, or coats your plumbing. When a filter is worn or clogged, the effects spread everywhere: dull water, higher chemical use, softer jets, and a pump and heater straining against restricted flow.
What separates a Unicel from a bargain cartridge is the media itself. Reemay uses a trilobal fiber — three-lobed in cross-section rather than round — which delivers roughly 45% more surface area than standard rounded filter fibers. More surface means more places to capture dirt and oils, higher dirt-holding capacity, and more time between cleanings. A semi-circular handle on top makes removal effortless, while the 1-1/2 inch SAE threaded bottom screws in for a tight, leak-free seal. Made in the USA.
Pro Tip: Check the bottom before ordering — threaded or open. Several 7-inch cartridges look nearly identical from the outside: same diameter, same semi-circular handle, roughly the same 10-1/2 inch height. What separates them is underneath. This 7CH-975 screws in with a 1-1/2 inch SAE thread, while similar-looking cartridges use a wider open bottom that simply seats in the housing. Turn your old filter over — if it has threads, you’re in the right place.
Brand
UNICEL®
