Knit upper Lace closure Active Ortholite Performance Insole 2mm Primus outsole Vivos are designed to let your feet move like feet. Strong, mobile feet that can spread, flex and feel – enabling proper posture, balance and movement, reducing pain and injury throughout the whole body, and enhancing your holistic health. The Primus Lite Knit’S Flexible Knit Upper, Made With Recycled Plastics, Adds Even More Mobility And Agility To The Beloved Primus Lite. The Same 2Mm Primus Outsole, With An Active Ortholite Performance Insole Made Of 98% Recycled Pu Foam, Makes It Perfect For Active Lifestyles And Controlled Workouts.