Features adjustable elastic headband; 7 blue/violent LED bulbs for tracking blood; 7 green LED bulbs for going to and from stand; and 14 white LED bulbs for all-purpose use. Bulbs have 100,000 hours of lamp life with an on/off button. Requires 3 AA batteries (included). Measures 3-1/8" x 2" x 2". Clamshell.