To activate your Black Wide Necktie with White LEDs, find the battery pack hidden behind the long tie, near its end. Flip the switch on side and bright white LEDs shine in 1 of 3 different LED modes: Flash, fast flash & steady light. To wear LED Tie, push the zipper tab up with thumb, pull UP on the zipper loop you'll find on top, place loop around head like a necklace, then tighten with ease. Dimensions (W x H): 4" x 18.5" LED Colors: 20 White Comes ready to use with 2 replaceable CR2032 batteries.