My rear tire went flat while driving on the freeway. The air pressure of this product has NEVER been changed. I relied on this product to protect myself. I have over 200,000 miles on my Harley so I want my monitor to be accurate. A less experienced rider would have fallen. When I noticed that the rear wheel was flat, I had destroyed the rear wheel. The monitor digits will NEVER change from their last barometric pressure reading. When the tow truck brought the defective Harley to the workshop, the workshop technician was even surprised that the monitor had not changed its last air pressure reading. VERY difficult to turn on and off. I mean, it's not hard to create a simple, effective on/off switch. VERY difficult to set up; The instructions aren't clear, so a lot of experimentation is required. Once turned on, the display works appropriately depending on the brightness of the sun. Limited mounting options. I heard (and saw) alarms. The sound is not audible due to engine noise, but visually everything is fine.