ASICS Women's GEL-Speedstar 4 Running Shoe 100% Mesh and synthetic Rubber sole The Rearfoot Gel Cushioning System attenuates shock during impact phase and allows for a smooth transition to midstance The Racing Trusstic System is a lighter weight Trustic System designed for faster turnover The open mesh upper provides excellent comfort and breathability The asymmetrical lacing design is an anatomically correct lacing environment that reduces potential for irratation and provides improved comfort and fit