2/package; Bright LED illumination; Glow mode - compact, convenient illumination; Twist on/off; Weather resistant * Each See"Em includes replaceable 1 x 927 3V lithium battery; Battery Run time: 24 Hours * Easy to attach and remove on most common spoke types - oval, round and bladed (flat) * Twist it, tie it, reuse it * NOT FOR USE WITH CARBON SPOKES