Are you looking for high demand for your observation experience and effectiveness? Or astronomy enthusiasts? Our 66° ultra-wide angle astronomical telescope eyepiece is made of high quality optical glass material for a clear field of vision and excellent contrast, giving you a good opportunity. Product Specifications: Material: Optical glass and metal; Focal length: 0.2 inches (6 mm); View: 66°; Insertion diameter: 1.3 inches (31.7 mm); Weight: Approx. 4.3 oz (110 g); Color: Black; High-grade material, delivers clear vision and superior contrast; Astronomical telescope eyepieces are made of high-quality optical glass material for clear vision and superior contrast.Slide to the 1.25 telescope eyepiece using a buck adapter can be directly attached to eyepieces with a diameter less than 31.7mm (1.25") for mounting the camera body. [New Optics for Better Performance] The optical system uses high definition lantern type high refractive index low dispersion glass. The high optical technology allows the image to be flat and corrected chromatic aberration, and the image is sharp.Recommended for those who demand high demand for observation experience and effectiveness, or for astronomy photography. (2.6 inches (66 mm) eye relief) This eyepiece has an impressive 66° field of view and 0.24 inch (6 mm) eye relief, giving you outstanding strength and ease of viewing, allowing you to enjoy powerful star images with a wide field of view.Observation, observation, or use different purposes, you can pull out the telescope without any extra capacity. Compatible with daily waterproofing: This eyepiece has a high JIS protection rating, and is compatible with daily water resistance.You can use it safely even if it gets wet at night dew at night.(Not for underwater use)Recommended for customers seeking high demand due to observation experience and effects. Note: Please do not use in water. Please be aware that there may be slight differences in size and weight.