The Nike Free Metcon 3 combines Nike Free flexibility around the forefoot with Metcon stability in the heel to help you get the most out of your training session. A flat, wide heel creates a stable base when you’re lifting. Nike Free technology in the forefoot creates flexibility for agility moves and sprints. Rigidity up the sides helps support side-to-side movement. A softer foam core cushions your foot, while a firmer outer layer is durable and supportive.