26-08-2013, 08:18 PM
I've got to say I think I might have to concede that I am wrong. I have had a huge read through a variety of sources (including the PNLD) and the only thing I haven't read is the actual British Standard document. So it looks like the document I'm sure I read has gone or been repealed (or otherwise I'm imagining it). I cant find any details on the spec of the material it just states it must be retroreflective. I guess that means that both metal and stick on plates are perfectly legal (as long as they otherwise conform to the regulations)