Bright Teflon coated fiber optic laces are fun to wear anytime and anywhere. It's also great for night jogging safety, parties, sporting events and holidays, or just to stand out in the crowd and be noticed. They will stay lit for up to 38 hours before needing new batteries. You can turn your Laser Tron Laces on and off, and even set them double flash. Best part of these laces is that they are weatherproof, heat resistant and washable. It can even be stretch to make them longer or cut them to shorten the length for smaller shoe sizes without affecting the special lighting capability.