On a countertop, the June Oven (1st and 2nd generation) needs 2 inches of space on each side and at least 4 inches above for proper air circulation. A plastic bumper keeps the back from touching any wall. Make sure all perforated vents are clear.
You can build the June Oven (2nd generation) into your kitchen open cabinet as long as there is nothing in front of the June Oven and the following spacing requirements are met. June requires 2 inches of space on each side, at least 8 inches of space behind it and 8 inches of space above it.