Features of the Merrell Women's Siren HEX Q2 E-Mesh Shoe Engineered mesh Upper Bellows tongue keeps debris out Kinetic Fit tri removable contoured insole provides light support to all three arches of the foot Q FORM 2 Dual-Density Midsole with heel-centering Technology provides genderengineered alignment and comfort Merrell air cushion in the heel absorbs shock and adds stability 3.5mm lug depth Outsoles root themselves in Performance designs and materials to deliver durable, Highly slip-resistant traction on wet and dry ground and over mixed terrain, releasing dirt and debris with specialized lugs Long-lasting M Select FRESH prevents sweat and moisture from aff ecting the freshness of your shoes Antimicrobial agents penetrate and disrupt the reproduction of the odor causing microbes in your shoes Alignment: Gender-engineered Dual-Density foam Midsole is properly sequenced into quadrants to help guide the foot, promoting a comfortable, efficient stride on the trail Stability: Heel-centering Technology compresses on heel strike, creating a pronounced heel cup, which keeps the heel centered, absorbs shock and stabilizes the foot Support: Kinetic Fit tri insole works with the natural movements of the foot to provide stability to all three major arches during athletic activity