Secure stainless steel carabiner light attaches to keys, zippers, jackets, backpacks, sleeping bags, tents, dog collars, etc. See and be seen. Glow mode (press once) is a bright LED area light, flash mode (press twice) is for safety and signaling. Water-resistant. Dimensions: 1.25" W. x 2" H. x .75 D. Weighs 6 oz. (2) 2016 3V batteries included.