They are ordered. FWIW the way they monitor pressure is neat. You do not order them to a specific pressure, but you do inflate the tires to the correct pressure. Then, you install the caps and from that point on the caps are calibrated for that specific pressure. They cannot be changed.

As Ben pointed out to me, I am finally getting LEDs on my bus. They will be on the valve stems, but will not show unless my tire pressures drop.

Eat your hearts out LED guys. The perfect LEDs do not show.