Can anyone answer my dim question about bits?

[Mirage]

New pony has a happymouth snaffle which needs replacing.None of the 3 equestrian stores near us has any the right size in stock,so I'm searching ebay.The thing is,I don't know how the bits are measured.Is it from the outside of bar to the opposite outside,or from inside the ring to the opposite inside? I'm at a bit of a loss as none of the sizes of the ones on ebay seem to match the one I have.
Thankyou for any help,I'm baffled.

When I measure I lay the bit flat and put the tape measure on the top measuring from outside to outside so if it was an eggbutt snaffle i would include the eggbutt part not just the part that goes through the mouth
Hope this helps
Probably just confused you more!

I measure the bit in the mouth...all mine in neule schule bits.

Happy mouth bits are also measured in cm rather than inches, so you need to look out for that.
I came across that when I bitted my pony. Went to the tack shop all prepared with the measurement in inches and couldn't work out the conversion into cm in my head
You could try measuring the pony instead (that's what I did in the end, because I was in the same predicament as you!!) Get a bit of string (or good old bale twine) and pop it in pony's mouth where the bit sits, mark the string on each side by the edge of pony's lips, measure, et voila-you have your bit size.
Thinking about it now, I almost certain that you measure the part of the bit that sits in the pony's mouth.........maybe somebody else will know!

You need to measure the inside ring to inside the opposite ring. If measuring the mouth instead you should add 1/4inch to the measurement for comfort. Just googled happy mouth snaffles and they seem to have them in stock at Frogpool Manor (no idea if they have the size you want) but i've been to this shop before and the staff are great so i'm sure they can advise you and they've posted stuff out to me before if you're not in the area.

I measure the inside too.

Hurrah! I knew that you lot would be able to help-thankyou.I have just been to a tack shop near where I was working this morning and bought one.The assistant there was very helpful and pointed out that you put it in the pony's mouth the opposite was to which they curve,as there are some raised letters on the bit that can feel rough in the mouth.That info was invaluable as I would have put it in the wrong way round.Now I've just got to reassemble the whole lot before our first ride.