GlowHERO LED Clip on Light - 2 Pack - GlowMarker By Versatile Clip and Go High Visibility Marker Light DUAL SIDED GLOW: The GlowMARKER shines bright highly visible light one both sides to make sure you are visible. CLIP ON VISIBILITY: This Glow Marker is the most versatile night time visibility product you can buy backed by GlowHERO. SHEDS WATER: This light up wearable is water resistant TPU plastic so it will work in light rain without fail. LIGHTWEIGHT & FLEXIBLE: At only 1 ounce these are the lightest forms of gear to keep you safer at night. REPLACEABLE BATTERY: The Clip on safety marker requires a single Cr2032 battery for 80 hours of use.