Mammut Aenergy Trail Endurance Ultra Low GTX is a waterproof, endurance-focused trail running shoe designed for mid-to-long distance runs. It pairs a GORE-TEX lining with Flextron PRO propulsion for strong energy return and reliable traction on technical terrain. Key attributes: Black | White | Textile / Synthetic | Waterproof (GORE-TEX Footwear lining) | High traction Vibram Megagrip outsole with Litebase | Dual-density cushioning (Mammut CORE Ultra + CORE Plus) | Flextron PRO propulsion plate for energy return | PFC-free DWR | Base Fit midfoot structure and lacing system | Ortholite insole for lasting cushioning | Ergonomic memory foam heel pods for secure heel lock | Standard lacing | Low-cut (Ultra Low) silhouette | Semi-sock tongue construction | Rocker profile for smooth heel-to-toe transition | 360° TPU reinforced rand for rock/debris protection | Dimensions & fit: Weight (US 9.5): 330 g | Stack height: 38/30 mm | Insole height: 5.00 mm | Heel drop: 8 mm | Base Fit — engineered midfoot support with secure lacing system | Standard lacing | Composition & care: Upper / Outer: Textile / Synthetic | Lining: GORE-TEX Footwear | Midsole: Mammut CORE Ultra + Mammut CORE Plus foam | Outsole: Vibram Litebase Megagrip | Insole: Ortholite | Reinforcement: TPU rand