The reins loop through the bit ring and throught the wee square metal ring that is on the end of the reins (so need to be separated at the middle, which will have a normal buckle fastening on the other end of each rein that you do up after they are on the bit rings)
Would be much easier to show or demonstrate than type, but dead easy to put on!
Lots of "racing" reins attach similarly, although they usually have a leather loop that the rein passes through. I have a pair of those and I love them.
Loop attachements very common in Germany, especially on jumpers.
Is there a reason they're popular in racing/SJ or is it just fashion?! I like the fact there's less fiddling with buckles or billets when (occasionally!) cleaning the bridle, but can't think of any other reasons!
ive got an old book that calls that fastening monkey up a stick, and says that is an old name for it.
it was (is?) popular in racing as it is deemed a very secure fastening as there is no buckle/metal to fail at high speeds.
think it went out of fashion generally years ago
monkey up a stick is the plain leather loop though, havent seen the metal loops before