Euclid High-Quality All-Makes Parts are designed and engineered for trusted performance with exceptional quality and value for independent distributors and their customers. Euclid is an established brand that customers have trusted for over 75 years. Euclid parts are tested for performance to make sure they live up to their name. They deliver exceptional quality and value for commercial vehicles that are in the second or third stages of ownership. Euclid. The Most Trusted Name In Truck Parts.