The Prio is the most comfortable shoe for everything you do. Whether youre out on a run, trying out a new trail, hitting the gym, or toeing a slackline, youll love the Prios combination of freedom and protection. The Prio uses the same 5.5mm FeelTrue® rubber as Xero Shoes' Z-Trek sandal, so you get great protection while still getting the ground feedback that your feet love. The optional 2mm insole lets you have more or less of abarefoot feeldepending on your mood. A womens 37.5 is only 184 grams eachyoull barely notice you have them on. Huarache sandal-inspired reflective heel and instep straps hold your foot securelywith or without sockswhile keeping your toes free to move. Plus, the Prio is made from 100% vegan-friendly materials.