This is a compact enclosure for the Radxa (or Rock) Zero3W that includes a maskrom plunger, and snap-on lids (choice of solid or opening for GPIO access). The case allows for insertion of a 30mm x 30mm x 10mm fan powered by on board 3.3v or 5 vdc. Design allows for addition of 4 finned heat sinks:

1. 20mm x 30mm x 6mm to be inserted below board to cool eMMC.
2. various heatsinks mounted on top of board hot components.

There is also a plunger to depress the maskrom button accessible on the bottom of the case.

Caution: only run the fan from case 3.3v (pins 1 or 17) or 5.0v (pins 2 or 4) and any ground. Other GPIO pins do not have sufficient power to run fan; you'll BREAK the GPIO pin. Fan air routed over fins of all heatsinks. My testing under load lowers temps by 20 C.

After printing, remove the support structure in lower cooling cavity and thoroughly clean out and smooth plunger cavity. An 30mm or longer 3mm to 5mm screw can be used to ream the plunger cavity. Also, smooth surface of the plunger. Plunger must move freely and bottoms out by gravity.