Just expose the collar to light for a time before your walk (the brighter the better), and it will still be glowing by the time you get back.

• Nontoxic durable material
• Snap-Lock clip
• Glows for hours
• Charged by UV light
• Great for nightly walks, night activities and sport

X-Small   5/8" x 11-14"
Small       5/8" x 13-16"
Medium   5/8" x 16-19"
Large      5/8" x 19-22"
X-Large  5/8" x 22-25"