Beware the Boss Mare! Whether you are someone's boss, you own a boss mare, or are just a force to be reckoned with, this t-shirt is for YOU! This premium quality heather t-shirt is made of a soft blend of 52% Airlume combed and ringspun cotton and 48% poly. It has a vintage worn-in feel right out of the box. Printed in the USA by a fellow equestrian, this tee features our popular original Boss Mare design.