The therapy pet organization I that I was with provided a 'uniform' vest for my dog - this way they were all the same and easily recognizable. Had to go in and have my dog measure and fitted! It was a lightweight Aqua Blue dog coat- looked very official though.
The organization that you will work with will let you know what is allowed/recommended for your dog.
Gryffon Vom Wildhaus
BH, OB1, TR1, AD
Rottweiler/Hairy Dog mix?? 2004-2015