Hi Mikey. I was prescribed with the Somaerect response 2 kit many moons again. It’s a fantastic pump and kit but the rings included were rubbish. On a separate prescription I got silicone rings with wing-tabs from the same company imedicare. The inside diameter is no more than a polo mints 😬 but they work a treat. They had X Y or Z on them. I still use the pump for regular exercise but rarely used the rings for intercourse. Just lots of gentle use regularly