Slightly larger than a quarter, this compact ultra bright white LED is really amazing. Simply squeeze the center and the Pulsar provides reliable light. Hook it on your backpack, bookbag, or keychain for instant light. Comes with white LED, 2 lithium coin cell batteries, and a stainless steel split ring. Weighs 7 grams with batteries. Batteries last 12 - 14 hours, bulb lasts 10,000 + hours.