Welcome to US Replacement Parts "USR PARTS" = QUALITY + AVAILABILITY + PRICE USR Parts specializes in quality replacement parts for Caterpillar® and Komatsu® construction and mining machinery. Our focus is to provide customers with high quality replacement parts at a great value. Every choice you make has multiple impacts. At US Replacement Parts We know your business demands more than just quality products. That's why you can count on the USR Parts® network to offer the additional resources, reach and know-how that add value to your operation and contribute to your success.