Light sensitive auto ON/OFF- To help you to conserve battery power when the light is not needed. Waterproof to IPX 4. Light Memory Mode: Stay on the same mode even when you turn the light off. Lumen and Run Time are tested under ANSI FL-1 Standard. Daylight Flash Mode: Making a cyclist more visible during the daytime. Battery capacity and charging indicator.   Specification 1 XP-G3 high brightness LED. Rechargeable lithium polymer battery (3.7V  1050mAh). Mode memory function. Day flash mode. 4 steady modes, 4 flashing modes. Quick release unversal bracket fits all round and AERO style bars. Mode indicator. Battery capacity and charging indicator. Automatic fully charged cut-off system. High precision optical lens. Recharge time 2.5hrs. Water Resistance (IPX 4)  . Size (W x D x H): 71 x 43 x 25mm. Weight: 0.066Kg / Packing & Package: 0.1Kg.   Lumen Output: Mode1: 400lm – 2.00hr. Mode2: 250lm – 3.30hr. Mode3: 130lm – 6.30hr. Mode4: 70lm - 12.00hr. FL1: 40lm – 80.00hr. FL2: 130lm – 25.00hr. FL3: 500lm - 13.00hr. Day FL: 500lm – 40.00hr.