Reins that split in two for use on a curb bit - what are they called?

[Snowfilly]

I remember seeing these in a very old book and now I’ve gained a pair I don’t know what they’re called!

Normal reins that have a buckle about 6” before the bit and another strap coming off them so they fasten to both rings.

This pair have billets and there’s several holes so the joining buckle can be adjusted.

Any ideas? They came with an ancient Swales Pelham.

 

[saddlesore]

They are just called split reins ?

 

[Elf On A Shelf]

Split reins, most often used by kids in the show ring so they don't have the hassle of 2 reins to deal with.

 

[SBJT]

Split reins

 

[Snowfilly]

Thank you all! I was over complicating matters as normal.