Portable: Helmet Light is compact in size and easy to carry. 2 Light Modes: Constant light & flashing light 2 modes, you can choose the light mode according to different . Waterproof: The Survival light is waterproof and highly applicable. Full- Covered Hook & Loop: Hook & Loop on the back of the lifeguard is fully covered for a stronger adhesion. Battery Loading & Unloading: Tear off the silicone edge on the back; remove the battery unit after removing the screws; replace it and put it back in its original position, and then glue it in place.