I ordered a high powered HK1 Android Box. It performs great, but has a flaw. The bottom has vent holes and surrounding them is the base of the device. It traps heat and this thing gets pretty hot. This might work for other round Android TV boxes. The radius is 50mm (100mm diameter). PLA isn't too resistant to heat, so if it fails, I will print with ABS.
100mm diameter. It's a simple design, print how you see fit. Made in Fusion 360. Make sure you print it upside down. The flat circumference will be on your plate.