Features:1. Made of good-quality aluminum alloy, solid, durable and corrosion-resistant.2. Black anodic oxidation treatment surface to prevent unwanted reflections.3. Support connecting with 2 inch telescope eyepiece and astrophotography filters, preventing damage to your telescope accessories.4. Equipped with two clamping screw with brass locking wing screw, prevent accidental slippage and keep telescope safe.5. Lightweight, small size and portable.Specifications:Material: Aluminium AlloyColor: BlackThread Diameter: 2 " M48*0.75Application: Telescope EyepieceTop Ring Diameter: Approx. 5 cm/ 1.97 inchBottom Ring Diameter: Approx. 5.9 cm/ 2.32 inchTube Length: Approx. 60 mm/ 2.36 inchTotal Length: Approx. 9 cm/ 3.54 inchPacking List:1 * Telescope Eyepiece Extension Tube Adapter