SAFTY BIKE REAR LIGHT 1.MATERIAL:SILICA GEL COVER & PLASTIC. 2.USE 2XCR2032 BUTTON BATTERY 3 SINGLE LED,SUPER BRIGHT. 4.CONSTANT MODE/FLASHING MODE 5.SIZE 20MM 40MM 6.CAN BE SEEN FROM UP 500 METERS 7.UNIVERSAL FITS,BULID IN PARABOLIC REFLECTOR. 8.SEAT POST MOUNTING CLIP 9.CAUTION: 1)CAREFULL INSTALL BATTERIES,MAKE SURE THE PROPER POLARITY. 2)DO NOT TURN THE LAMP ON/OFF WHITE RIDING THE BICYCLE. 3)DO NOT LOOK DIRECTLY TOWARDS THE LIGHT. PACKAGE:BLISTER CARD QTY/CTN:240 CTN SIZE(CM):72.54342 G.W.(KGS):15 N.W.(KGS):13