Check the listing for details. 2 Inch Variable Polarizing Filter Lens for Astronomical Telescope Eyepiece. Condition: New. Listed at 18.89 USD. Features:1.The 2-Inch variable Polarizing filter acts like a dimmer switch for your telescope.2.Adjust the amount of light transmission from 1% to 40% by rotating the filter housing.3.Reduces brightness of the Moon or planets for great clear viewing.4.Finer control of the image brightness compared to a standard fixed-transmission telescope filter for optimal performance.5.Fit standard sized 2" eyepieces and accessories. Descriptions:Premium Quality Metal Rim and Optics Glass Lens.Its compact, lightweight body makes it an ideal travelling companion. Specifications:Type: Variable Polarizing FilterMaterial: Optical glass lens + Aluminum FrameShape: RoundBarrel diameter: 2 inch Package included:1 x Filter Notes:1. Please allow 1-3 cm measure error.2. The color of the actual items may slightly vary from the above images due to different computer screen, thanks for your understanding.