This standoff is for a 36mm flight controller and ESC with 30.5mm M3 hole spacing, the base standoff height is 3.5mm. The edges are filleted to reduce the risk of damage to wires. Note the M3 holes are 3.2mm which should allow for use without drilling but I have not printed this off yet so any changes will be updated. The second standoff is to go between a 4in1 ESC (normally at the bottom of the stack) and the Flight controller (at the top). The spacers are bevelled and intended to be used with rubber O-rings washers (probably 4mm x 2mm) to provide damping. I will post pictures when finished but I am waiting for the O-rings and mounting M3 bolts to arrive. The parts were designed using TurboCAD 2016.