Material: Plastic soft rubber and metal.Application: Connect mobile device to telescopes to take photos. Eyepiece bayonet connection: Compatible with telescope whose eyepiece outer diameter is between 26-43. 5mm suitable for mobile phones with a width of 62-105mm such as Huawei Samsung Apple Xiaomi etc. Rubber sucker connection: Connected to mobile device with camera or video function such as smartphones tablet computers. DESCRIPTION: 1. Eyepiece bayonet: Internal diameter is between CM-8L:38. 5mm-43. 5mm. 2. Rubber sucker: Connected with mobile device. 3. Lock catch: Rotate clockwise to narrow eyepiece bayonet or anticlockwise to expand eyepiece bayonet push up to fix eyepiece bayonet. 4. Fine adjustment screw: Loosen to adjust eyepiece bayonet. Note: 1. Preferentially take photos with touch screen camera if your mobile device has this function. 2. Preferentially take photos with center focus if your mobile device has focus camera. 3. Keep it away from fire and heat. 4. If rubber sucker is stained with dust rinse it for reuse. 5. Do not scratch rubber sucker with sharp objects or its service life will be affected.