I purchased a AINOPE Gravity Phone Holder (https://www.amazon.com/gp/product/B089LDX88M/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1) for my Microsoft Surface Duo. It isn't quite wide enough so I created these ears so the phone would fit in the mount. Uses 4-40 screws and nuts. Had to shave down the posts on the ear a little bit. Also used some locktite to hold the screws in loosely so the springs can still make the ears spin. I also had to drill one small hole after for the spring. Works great.