The Orange Pi5 Max can run a little hot under some workloads, adding a heatsink and fan to it will keep it from throttling the CPU.
Most heatsinks will work, the 25x25x7mm is a good fit for this case. Any taller than 7mm and there might be some clearance issues.
The 40x40x10mm fan is a 12v fan, when powered by 5v, it will spin slower, but still moves plenty of air. Power it via the +5V pins on the 40pin header. Note: The fan will spin as long as there is power on the USB power port--even if you shutdown the Orange Pi, the +5V pins will still be powered.
If you need wifi, please use the top cover with the antenna holder.
No tools or fasteners required, everything is a friction fit.
https://www.amazon.com/ANVISION-Bearing-Brushless-Cooling-YDM4010B12/dp/B0711FVD48/ref=sr_1_1?sr=8-1
The author remixed this model.
Cutout for 40mm fan, and side clip for wifi antenna.