Pergear Fisheye
https://www.amazon.com/Pergear-Pancake-Fisheye-Compatible-Z50%E3%80%81Z6%E3%80%81Z7%E3%80%81Z6II%E3%80%81Z7II/dp/B08SK5VGCF/

 【Compact & Lightweight】Rugged all-metal body structure, weight only 0.18lb/80g.
【Optical structure】5 elements in 4 groups, aperture range: F/8.0.
【Extra-low dispersion lens】This lens features 3 extra-low dispersion (ED) elements, which helps to correct chromatic aberrations or optical color defects, giving a nice color rendering in a variety of light conditions.
【Unique manual focus lever】Due to its slim size design, The lens adopts a unique manual focus lever. with the length scale and smooth design, you will easily get used to it after a short time of learning.
【Kindly note】the manual focus lens can't be recognized by the camera automatically, please change the camera setting to "release without lens" before using this lens.