Fully compressed express belt of advanced (red) circuits. Requires 2 belts of copper, plastic, and electronic circuits each. The productivity modules in the copper wire assembly machines are optional, but will obviously result in less copper consumption. Filter inserters are to mark the inputs and output. Requires inserter capacity bonus 7 (might work with less, I haven't tested) to fully compress. (I feel like it's much larger than it needs to be. If you know of a more space efficient design, feel free to let me know.)