Step 104: 12-Point Triple Square or XZN
Other names used for Triple Square screws and drivers are "Double Hex", "Double Allen", and "Aircraft Screws". Despite this, "Double Hex" and "Double Allen" are misnomers. The recess in these bolts is actually (as the name suggests) made of three squares, not two hexagons. The corners are 90°, not 120°. As they are not double hexes, an Allen key will not fit them properly.
Common sizes are 6, 8, 10, and 12 mm. Triple square drivers can be purchased at auto parts stores and through automotive tool distributors.[[br]]