Thanks for the replies....
...I will admit to forgetting this site has a search function (que "doh" sound & slapping of head)
Leonnie's link & info is great and very informative....
...right, I'm off to cut a chunk (well, page 68) out of my GYO mag and send off for 5 x "T65" slips & 5 x "Beauregard Improved" slips, and all for £8.99 inc P&P....
Once again, thanks.