Molten plastic is injected into steel molds to make the front and back halves of the case, the button caps and the triggers. Each shot cools in seconds and pops out at its final shape.

Machines print solder paste onto a circuit board and place the processor, the wireless chip, the motion sensors and the charging circuit, then melt everything into place in a reflow oven. Bare copper pads are left wherever a button will press.

A molded silicone sheet with a dome over each button sits on the board. Pressing a button squashes its dome until a carbon pill underneath bridges two pads and closes the circuit. The dome springs back on release.

Each stick module sits on two sensors at right angles, one reading left and right and one reading up and down. Most use potentiometers, which wear with time and can cause drift, while some newer designs use magnetic Hall effect sensors with no rubbing contacts.

A small motor with an off-center weight goes into each handle. The left one is often larger than the right, so a game can mix a deep shake with a fine buzz.

Wireless models get a rechargeable lithium-ion cell plugged into the board. The halves are pressed together around the board and fastened with screws hidden under the grips or labels.

Each finished controller is paired with a tester that checks every button, both sticks, the triggers, the motion sensors and the motors. The stick centers are calibrated before boxing.