I was wondering what the sizes from corner to corner the holes in the SpeedyBee F405 AIO 40A were and if it would be able to fit on my 3.5 inch drone
Mounting Holes: The board uses a 25.5 x 25.5mm mounting pattern with 2mm hole diameters.
Board Dimensions: It’s a compact 33.0mm in length and width, and stands 8mm tall.
Now, whether this will fit your drone depends on your frame’s design. Many 3.5-inch frames are designed to accommodate this mounting pattern, but some might not. So best to double check, but hopefully this helps!