The nebula cob rear light generates 100 lumens of light from and compact and light weight design 1 pce 50 chip rectangualr ring cob high brightness led rechargeable lithium polymer batter 37v 800 mah cnc aluminium heat sink 8 modes quick release patented universal bracket fots all round and aero bars 2 x o rings 20 35mm amp 35 52mm quick releae saddle rail mount included low battery charging amp fully charged indicator automatic fully charged cut off sid evisibility ipx4 water resista