Great for night visibility, parties and special occasions, each set comes with two laces and two battery pack locks to keep the laces intact and your shoes tight. Choose from 3 light modes: fast flashing, slow flashing, or steady. Requires 1 button battery per shoe lace, included. Laces last for over 50 hours of flashing. So easy to put on and take off, you'll want a set for each pair of your shoes. Choice of blue or pink.