Come and see our amazing products. Made of silicone shell, light inside, includes one button battery. There are three models of the light. Click the button once, it will light up always, click again, it will flash fast, and click third, it will flash slowly, and click fourth, it will turn off the light. Easy to install quickly, without any tools required! 1 3/4" L x 1 3/8" W x 1 1/8" H, the price includes the shipping cost to CA, Qty over 20K by ocean. Pls confirm with us about the packing info, stock color and exact production time before placing your order.