I'll try to describe it first since I can't find the exact picture online to show you.
It is a straight elastic (wide) band, with a perpendicular leather attachment for the girth (runs between the legs). Holding it up it forms a T (isn't V shaped like the ones I'm used to). It has NO wither strap (like the hunting ones I'm used to). It also has removeable running martingale straps.
Now, this type of "T" style breastplate - is it supposed to fit more up toward the base of the neck and attach to the D rings on my saddle? Or is it meant to attach to the billets on the girth? I've seen jumpers like Nick Skelton and Arko with similar straight-across breastplates... but it seems like the tack shop photos are tight fitting (I'm guessing just to make the breastplate look nice in the photos) and I don't believe it should fit so tight as to restrict airways....
Any suggestions on how a straight-across breastplate is to fit? I assumed a fist width between his neck and the band but I'm worried about it fitting too high... so maybe it's supposed to attach to the billets?
Here's some photos I've found of ones that are similar:
Shires 4198 Eventing Elastic Breastplate this one is pretty close to what we have - mine naturally sits about the same place, maybe an inch higher.