Tooth-and-adaptor fitting system replaces force-fit retention system with a twist-on retainer, increasing the productivity of excavators from 60 to 400 tonnes and loaders from 70 to 350 tonnes. The MTGtwist locking solution uses an easy-to-extract conical pin that is very often reusable from tooth to tooth, held in place by an elastomer retainer. The fitting system distributes forces evenly across the adaptor for maximum strength. Tooth designs are optimized for better penetration, and employ more wear material for longer life. Adaptors are designed to protect the weld and the legs from lower and lateral wear and tear. The mechanical wear cap extends adapter life in abrasive applications.