I’ve just invested in the new ‘short’ cage for my CB-6000 (and I’m really impressed with it: much better more comfortable fit). But trying to get that fit right got me thinking about the relationship between the ‘rings’ and the ‘locking pins’. As we all know there are five (different size) rings and four (different length) locking pins. In general ‘comfort’ is dependent on the size of the ring and ‘security’ upon the size of the gap between the ring and the cage – determined by the length of the pin – used to trap the balls. If you number the rings 1 – 5 (smallest to largest) and the pins 1 – 4 (shortest to longest) there are 5 x 4 = 20 possible combinations but, I think, only eight different fittings. For example I’m currently using the second-largest ring, 4, with the shortest pin, 1, OR a fit of 4+1=5. You can put these into a table, but I have no idea how this is going to appear when I post it: Pin 4 Pin 3 Pin 2 Pin 1 Ring 5 9 8 7 6 Ring 4 8 7 6 5 Ring 3 7 6 5 4 Ring 2 6 5 4 3 Ring 1 5 4 3 2 Unless you’ve got balls like grapefruit, I don’t think anyone is going to be using the largest ring with the longest spacer, but equally unless you’ve got balls like grapefruit pips, I’m damn sure no-one will be wearing a smallest ring with the shortest pin (trying looking !). But this does seem to suggest there are eight possible ways to get a medium fit or either a five or six. I’ve no idea whether this is right or not – and would be very interested to hear from others – although I think it is. If so it could be used as a sort of Fitting Guide !