Telescope Lens Active Warmer with Fast Heating and Long Lifespan Feature Made of polyester material, durability and functionality * When photograph outdoors in cold weather, the large temperature difference between day and night may cause dew and fog inside the telescope or lens, affecting imaging and efficiency. Use the defog belt to eliminate fog and water, which can help more stable photography *Intelligent temperature control, faster heating, more uniform heating, longer service life *Powered by 12V mobile power supply (not included), connector type DC5521 *Suitable for astronomical telescopes of various calibers, camera lenses, bird-watching mirrors, guide mirrors, . Specifications: *Product Name: Astronomical Telescope Lens Dew Heater *Material: Plastic + Polyester *Size: approx. 530*50mm: Suitable for 130mm diameter lens;