I use Bernie's Pressure Pro monitors. Basically I've seen two types that might work.. The Pressure pro mointors tire pressure on just about any kind of tire... My Motor Home, and my Towed are both mointored
THey could mointor my lawn cart and bicycle as well if I wished (However that's getting a bit much)
They have detected the occasional screw in the towed's tire (hazard of where I used to work... Don't work there any more, quit last week)
The other one I've seen straps to the rim INSIDE the tire... IT will not monitor all kinds of tires though, some tires have too low a profile and damage to the monitor would occure, others don't have the rim width So it only works on some vehicles... Also the minotor is much larger and appears to be seperated from the receiver, making it difficult to move from Motor Home to towed (or other vehicle) and back.
Pressure Pro the minoitor/receiver is about 1/2 inch thick, perhaps 4-5 inches high and about 5-6 inches wide, mounts with either special mounting brackets (I assume from the design of the package) or common velcro tape which you can get at more stores than I can count (RV, Drug, Department, Sewing, Auto, and so many more I can't list them all) To move it you pull the plut, plug it in and optionally push the F/B button till only the tires you want to monitor are lit (multiple pushes often needed) to move it back... Same procedure
The system that straps to the tire also monitors temperture and can thus detect a dragging brake
IF, that is, it will fit on your ride