Feature: 1. SAFETY PROTECTION: Protects the digital camera lens or viewfinder from freezing due to cold fog and dew, allowing the device to function normally even when the temperature drops or the weather is bad at night. 2. THREE SPEED TEMPERATURE CONTROL: This lens heater has three speed temperature control for high, medium and low temperatures to meet different usage needs. 3. USB PORT DESIGN: You can connect it to a portable power supply or any other power supply device with a USB port, so it is very easy to use. 4. WIDE APPLICATION: The lens heater can be adjusted according to the size of the lens and easy to attach, suitable for most sizes of telescopes, viewfinders, digital cameras and so on. 5. HOOK AND LOOP FASTENERS: The lens heater is secured by hook and loop fasteners, which not only allow the heater to fit the lens, but also allow for quick removal and adjustment of the desired length. Specification: Item Type: Lens Warmer Material: Graphene Weight: Approx. 60g / 2.1oz. Package List: 1 x Lens Warmer