Regal 3300 Owner's Manual page 89

Engine & Controls
Smart Cylinder
Located on the front of each engine is the steering smart cylinder. It is
footprinted with redundant sensors to determine the steering response
to the wheel movement. If one sensor should fail there are back-up
ones on each cylinder. The stainless steel cylinder includes ORB fittings
with bleeders to purge air as needed.
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