On this fifth generation of our original running headlamp, we present a new kind of technology where the power cable is fully integrated into the head band. We call it Free Technology - a comfortable headlamp experience without distracting cords. No hassle - Just free the energy. The hybrid battery case can carry either a rechargeable pack or AAA batteries. It has grip friendly surfaces and holds an integrated red rear safety light - adding extra visibility. Trail Runner Free is lightweight and perfectly balanced, with smooth adjustments and a flat, soft textile extension cord that doesn't tangle.All FREE models feature Silva's Intelligent Light®- A wide beam in front of you and a long beam ahead of you FREE H model includes compact USB rechargeable hybrid battery with 1.15Ah. FREE Ultra includes compact 4.0Ah USB rechargeable battery with 4 step battery indication for long distance use, along with the hybrid battery case. The battery can be carried comfortably on the headband or, thanks to the extension cord, it can be kept warm in your pocket to save battery life.