Product features and benefits Rubber suction cup connection: The Gummisauger (rubber suction cup) connects directly to your mobile device for a quick, non-permanent attachment that keeps the phone aligned with the eyepiece. Universal eyepiece bayonet: Ocular bayonet fits eyepieces with an inner diameter between 22.5 mm and 48 mm, covering a wide range of common telescope, microscope, and spotting-scope eyepieces. Secure, easy locking: Turn clockwise to narrow the bayonet, turn counterclockwise to expand it, then press up to lock the bayonet in place. Simple, repeatable operation ensures a stable hold during imaging. Stable alignment for imaging: The adjustable bayonet and locking mechanism minimize rotation and misalignment, making it easier to capture photos or video through an eyepiece with a mobile device. Protective, non-invasive mounting: The rubber suction cup attachment avoids permanent modification to your mobile device or instrument and provides a soft interface that reduces the risk of scratches. What this product solves Eliminates hand-held instability when photographing through eyepieces by providing a firm mechanical connection between mobile device and eyepiece. Adapts a single mobile device to multiple eyepiece diameters (22.5–48 mm) without needing separate adapters. Simplifies setup and teardown so you can focus on observing and documenting rather than fiddling with mounts. How to use Position the bayonet over the eyepiece. Rotate clockwise to tighten the inner collar until the bayonet grips the eyepiece; rotate counterclockwise to loosen as needed. Press the bayonet upward to engage the locking position for a secure hold. Attach the rubber suction cup to your mobile device to maintain camera alignment with the eyepiece. Practical applications Telescope digiscoping: Attach your mobile phone to a telescope eyepiece to photograph the Moon, planets, or deep-sky objects while maintaining a steady optical alignment. Microscope documentation: Capture images or videos of slides through a microscope eyepiece for teaching, lab notes, or field documentation. Field optics and spotting scopes: Use with spotting scopes or binocular eyepieces to photograph birds, wildlife, or distant details without specialized camera gear. Technical specifications (as supplied) Attachment: Gummisauger (rubber suction cup) connected to mobile device Eyepiece bayonet (ocular bayonet) inner diameter: 22.5 mm – 48 mm Locking mechanism: Turn clockwise to narrow, counterclockwise to widen; press up to fix Notes Designed for compatibility with eyepieces within the stated diameter range. Follow the locking procedure to ensure a secure connection before imaging.