another bd question - numbers

No. Just any bridle number holder will do.
OH has the one that uses plastic letters with lugs on back which fit in to holes in the holder. Holder attaches to bridle with velcro loops. Now in its 5th year of use and has been brilliant.
 
My first one had elastic loops and I just couldn't get away with it at all. The one I have now I've had about 6 yrs and it has a slot in the top and bottom for throat lash to go through. Really simple to use and I highly reccomend. I saw one recently for £7.99 I think
 
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