Motion Pro is dedicated to producing the most versatile, unique and durable products for professional and home use. Motion Pro tools are designed to be simple to use, yet durable enough to withstand the harshest conditions. One of their goals is to offer tools of convenience. Do it right the first time with Motion Pro Tools. Fits most 520 and 530 standard and O-ring chains. Designed to press side plates onto the master link. Hex key wrench is included with tool. Perfect addition for tool packs. Made in the U.S.A.. Note: Does not rivet together rivet type master links.