1. It is recommended to use No. 7 900mA rechargeable NiMH battery， it can work nine hours of continuous function in the case of fully open.2. Laser Safety taillights Class IIIA level with international safety standards， but do not direct the shoot eye.3. using an adjustable snap lock ring (for 20-31mm diameter seatpost diameter)4. The five LED lights are really bright LED lamp5. Meet the IPX-II grade waterproof standard， tilt 15 degrees raindrops waterproof