Shower cartridge removal

Removing a round mixer shower cartridge can vary depending on the specific model, but typically, you'll need to locate and remove any cover or trim plates to access the cartridge. Once you have access, there may be a retaining clip or nut that needs to be unscrewed or removed to release the cartridge. It's essential to consult the manufacturer's instructions for your specific shower model, most of the manuals are easily found online.

Maybe a small grub screw holding it in place

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