I have a Kubota RTV 500    M.A.P.(Manifold Absolute/Air Pressure) Sensor.  I've seen them get hit, break the nipple off where tubing attaches, or simply get damaged over the years.  A section of the wiring harness plugs into it, and an air tube attaches to the sensor nipple and it sends important signals to the main ECM onboard Computer on RTV 500. It is one of several sensors on an RTV 500 that sends signals to adjust engine performance.  I do know it retails for approx $279-$322 from Kubota. Do you want it for a spare, to replace a broken one, etc.  Shipped to lower 48 states. Buy with confidence, I have sold on Ebay for over 15 years. I strive for positive feedback from buyers.  Thank you