Thanks Gary and to the previous replier- I know what it relates to in terms of pylon, and thanks for your references, but where do I find the 'big picture' meaning. Does the same apply for say r/c aerobatics, or glider....................is it fair to say that the components generally are moulded by way of a female mould and could comprise balsa, epoxy, carbon, kevlar, glue, devinycell,etc. I have yet to find what the industry may define it as. The local boat industry here defines ait s any moulded epoxy/ polyester product using strengthening components, that is moulded in a female mould, or over a male mould. Is that the only answer. Gary, I still have that hat for you- will you be in Germany next year? Trevor H NZ