Xero Men’s Running Shoes Excellent Condition Performance Training Shoe. We took our best-selling all-around f itness shoe, Prio, and made it sleek, elegant, and lighter weight (9.6oz/272g M9). Welded construction and a mesh upper make the Prio Perform ready for action and all-day comfort. A moisture-wicking lining keeps you cool, and our iconic tensioning system holds you securely during your training. The wider, foot-shaped toe box allows your natural balance, strength, and agility to develop while you put the 5,000 mile sole warranty to the test.