Yea the mains pipe is 15mm class C and ill be coming off in 15mm copper to ballcock so ill need a 15mm class C poly to 15mm copper. But what im saying is can you get class D mains pipe in 15mm 22mm 28mm ect, and since class D has a thicker internal bore can i use a compession fitting straight on class D or will i have to use a philmac fitting regardless. Thanks
