ASICS Women's GEL-Trail Sensor 4 Running Shoe 100% Synthetic and mesh Rubber sole Impact Guidance System employs linked componentry that enhances the foot's natural gait from heel strike to toe-off Heel Clutching System provides improved support and creates improved heel fitting environment, Trail Specific Outsole has reversed lugs provide uphill and downhill traction on all types of terrain Inner Lock Lacing System has asymmetrical internal straps comfortably wrap and secure the foot on the platform of the shoe, improving fit and stability Trail Sensor System enables parts of the midsole to decouple for optimal traction on uneven terrain Asymmetrical Lacing Design is an anatomically correct lacing environment that reduces potential for irritation and provides improved comfort and fit