Feature: 1. Wide Applicability: This dust cap is suitable for telescopic eyepieces, telephoto zoom eyepieces, astronomical primary mirrors or photographic sockets with M48x0.75 mm dimension threads. 2. Protects Lens: This dust cover effectively your telescope lens from dust, dirt, and other potential damage, ensuring clear and uninterrupted viewing. 3. M48 Thread: The dust cover is designed with internal threads and can be screwed directly on the thread of the lens interface to protect the lens more firmly. 4. Pefect Fit: The mold opening ratio of the dustproof lens cap is 1:1, and the lens cap fits perfectly with the telescope eyepiece to effectively protect the lens. 5. Material: Made from aluminum alloy, this dust cover is built to last. It provides long lasting protection for your telescope lens, making it a accessory for any astronomy enthusiast. Specification: Item Type: Telescope Lens Dust Cap Material: Aluminum Alloy Thread Size: M48X0.75mm Thread Depth: Approx. 4mm / 0.16in Package List: 1 x Telescope Lens Dust Cap