Item Type: Telescope Dust Cover Material: Aluminum Alloy Thread Size: M54X0.75mm Thread Depth: Approx. 4mm / 0.16in Package List 1 x Telescope Dust Cover 1ALUMINUM ALLOY CONSTRUCTION: Made of durable aluminum alloy, the dust cap is not only sturdy but also easy to use, providing long lasting guard for your telescope lens. 2M54x0.75MM SIZE: The dustproof cover adopts an internal thread design, which can be directly screwed on the thread of the lens interface, protecting the lens more firmly. 3PRECISE FIT: With a 1:1 ratio of open mould, the dustproof cover for the astronomical telescope magnifying lens fits perfectly with the magnifying lens, effectively protecting the lens. 4VERSATILE APPLICATION: Telescope lens cover is widely used, suitable for telescope eyepieces and telephoto zoom eyepieces. Its use is simple and can easily meet your needs. 5EASY TO USE: The telescope lens dust cap is designed for user convenience, allowing for easy installation and removal. It offers a hassle free way to ensure the cleanliness.