S
Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
As kozak says, just replace the entire lot. They're only about 100 odd quid, a new cartridge will be 50 plus anyhow.
*cough*
Reply to the thread, titled "need help identifying what cartridge is need for my shower as I can't get it outland" which is posted in Showers and Wetrooms Advice on Plumbers Forums.
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