I have noticed that several of the horses at my new barn sport this equipment under saddle. They run from the girth (between the front legs) through the bit ring to the dees on the front of the saddle. I asked about them and was told they were schmoekles (?) - a german training aid.
I’ve tried searching the term and am not having any luck. (I’m sure my spelling is wrong!) I would like to do some research on them. Any ideas?