1 - HD Lens - The eyepiece is made of high definition transparent blue film optics, the imaging is clear and bright, so you can see very clearly at night. 8X20 zoom monocular with a viewing angle of up to 8x and a 20mm objective lens for a clearer and brighter view. 2 - 21mm objective lens - This Mini Pocket Handheld Monocular uses high-end BAK4 prism. 12mm eyepiece with FMC broadband green film plating, can effectively eliminate the internal light dispersion of the glass, reduce internal light loss, high transmittance, more transparent field of view. 3 - Easy to use - The focus wheel can be easily adjusted with a single hand on the mobile phone, which is the most user-friendly bird monocular. The eyecup swivels up and down quickly and easily for optimal viewing with or without glasses, allowing your phone to embrace nature more clearly. 4 - Wide range of applications - This compact telescope is easy to handle with one hand and is ideal for quick observations. It folds to match your eye distance and is easy to focus. 8X20 zoom monocular for up to 8x viewing; use the 20mm objective for a clearer, brighter field of view. FMC multi-layer enhanced green film increases light transmission for brighter images and higher contrast. Field of view: 96M/1000M. 5 - One-handed design - light and compact, more portable, widely loved by the majority of observation enthusiasts