To activate your LED Shoelaces, remove pull tab & press button on top of the round battery house. Choose from 3 light functions: Fast Flash, Slow Flash & Steady Lights. NOTE: Sold per pair. 1 pc = 1 pair. Battery House Dimensions (L x W x H): 1.5" x 1.25" x 0.5" Shoe Lace Length: 42" Shoe Lace Color: White LED Color: Blue Laces come ready to use with 2 replaceable CR2032 Batteries. To change the batteries, just pop off the top of the battery housing, switch 'em out then snap it back on.