[Mr. X]

I believe the RA rubber comes from the USA, as does much of the rubber used by other companies. Fondueset did some research and found the industry experts in this sort of stuff were the companies than made rubber for castrating bullocks! I think most is produced by two companies in the US. [Perhaps we could coax the London Rubber Company to apply some of their expertise - Durex bands? Or Michelin in France? Pirelli in Italy?]

I agree, the RA rubber seems very dense and powerful. I liked their 16mm bands, plenty powerful enough for me. I find their 20mm rubber hardwork on my 90cm railgun & will switch back to 16mm when these wear out (if they wear out) - more than powerful enough for the UK.

Recently I got an Omer with 18mm bands. I know Spaghetti rates Omer rubber in the 18mm size. They seem quite powerful. Squeezing the rubbers, it feels to me like the Omer rubbers have a much larger hollow space in the middle than the RA rubbers. To look at, 18mm rubbers look about the same thickness as the 20mm RA rubbers.

Spaghetti and others rate Dessault rubber, which has different characteristics so I am keen to try that next. Bulk rubber would be my preference, with a Dyneema wishbone. The screw-in wishbone caps seem to allow water into the rubbers.