Ones in stock are specifically made for wide 8 tooth and 14” long rasps, like a Bellota Raptor Plus. 
 
I’m not a farrier for other peoples horses, just our own but I trialed these covers with my own rasps and it is working well. It just helps keep the rasp teeth from getting damaged by the other tools in my hoof care tote and helps keep it from getting rusty from moisture. Also helps you keep from skinning yourself on the teeth while it’s not actually in use.
 
I will be making some for narrower and possibly longer rasps (with some different colours leather to), I just will have to trial those size covers first. The rasps teeth do not seem to wear on the leather if you make sure it is just the right size for the specific rasp.