Feature:1. Adopting aluminum alloy material through craftsmanship, it is durable and corrosion resistant.2. The inner wall is treated with extinction processing to prevent the radiation from affecting the imaging.3. It is used to connect the camera to astronomical telescope with stable performance and high reliability, which is a very practical accessory.4. Easy to install and flexible to operate, which can effectively save your time and efforts.5. Light in weight, it will not burden your device when using it, and it can protect your camera.Specification:Item Type: Adapter RingMaterial: Aluminum AlloyProduct Color: BlackInternal Thread Depth: Approx. 6mm / 0.2inExternal Thread Depth: Approx. 4mm / 0.2inFlange Distance: Approx. 8mm / 0.3inClear Hole Diameter: Approx. 45mm / 1.8inProduct Weight: Approx. 27g / 1.0ozMount: SCT (M51x1mm), M48x0.75mm Package List:1 x Adapter Ring