these are the blue ones that pies is on about, they are worth they wait in gold i do have some of the red handles on my tank, and yes very hard to turn but hopefully you shouldn't have to use them that much when set up
depends on the size 20mm 25$ 25mm37$ you might be able to get them cheaper if you got some good contacts got these from Mico Plumbing
but they got them from Asmuss Plastic Systems LTD
34 ARRENWAY DRIVE, NORTH HARBOUR
Phone 094772320
www.plasticsystems.co.nz