Waterproof compression-molded foam midsole with HUBBLE® heel and SwallowTail™ Quick-lace metal top hooks Abrasion resistant toecap and heel Heel pull tab Rubberized EVA midsole Molded PU sockliner with 50% soybean oil Specs Weight:   16.80 oz Heel-To-Toe Drop:   6.00 mm Volume:   807.00 cm 3 Spring Measurement:   29x34 mm