Pi 4 40 mm Fan Cooling Bridge
A standoff bridge that suspends a 40 mm fan directly over a Raspberry Pi 4B / 3B+, with a 32 mm shrouded duct collar aiming the air at the SoC instead of letting it spill sideways. 74 x 64 mm plate on four 18 mm legs that clear the USB/Ethernet stack, 58 x 49 mm M2.5 board pattern with captured nuts at the board end, 32 mm square M3 fan pattern, plus side exhaust vents and a 26 x 4.5 mm slot for GPIO ribbon or camera flex.
electronics raspberry-pi 40mm-fan cooling