TO bad we can't see inside of this horse's mouth. This looks to be a tongue depressor or a anti-lolling bit. Perhaps a modern version of the Herman Riggs anti pulling "bit" that is typicaly attached to a snaffle bit inside the mouth and helps keep the horse from leaning on it.
It is more than likely a tongue depressor (which is my first guess). This horse must be realy cheeky on getting his/her tongue over the bit. With the use of the grakle and the depressor (which most tongue depressors have a strap going from the bridle rings and under the chin to keep it in place, as shown in the photo of Tracer's post and is missing in the photo) I say is a bit of an overkill. But I have known some cheeky horses with great talents on tongue flipping over bits even with juba ports in conjuction of a dropped noseband. Actually the grakle and the anti lolling bit makes more sense in theroy.
Overcheck bits are attached to overcheck reins in carriage or driving and with ponies that tend to "graze" while being ridden and pull thier little riders forward overcheck reins/lines can be attached to fronts of saddles to aid in stopping this.
"The question is not, can they reason? nor, can they talk? but, can they suffer?" Jeremy Bentham
Last edited by ZaneyZanne123; 12-11-2013 at 05:11 AM.