Merrell All Out Crush Tough Mudder Trail Running Shoes - SS17-11 - Black Synthetic Waterproof Upper - Waterproof upper that is designed to protect the foot from water. Drainage Ports - Prevents puddles from occurring within the shoe. Abrasion-Resistant TPU Film - Provides lightweight protection. Protective Toe Cap - Added to provide that bit of protection whilst attempting the bigger obstacles. Reflective Detailing - Provides enhanced visibility.