This is a toothpick quad with 8.5mm motors and 65mm props. Its made to house a whoop-sized FC (26 x 26mm).
The battery holder needs to be mounted with the opening towards the back so you can access the USB port. I installed a BeeBrain V2 that I had lying around. I made my own connector out of balance plugs but they only have 2 pins (solid pins) which result in less voltage sag. I am using a 600 mAh battery with my custom plug mod to get around 3:30 - 4:00 min of flight time with plenty of power.
Parts:
BeeBrain V2: https://tinyurl.com/2p8zjb37
Props: https://tinyurl.com/3nuec3nb
8.5mm Motors: https://tinyurl.com/2p8mf44e
Battery Connector Plugs: https://tinyurl.com/yuhhj469
Battery: 40c minimum
The author hasn't provided the model origin yet.