Georgeandkira,

I bought a model 20257 Schrader Bridgeport. This unit requires it to be hard wired into the vehicle. Here is the link you can cut and paste.

http://schrader-bridgeport.com/brochure.cfm?brochure=5053&location_id=11404

The easier set up is battery powered and is model 20256 if wiring into the car is not desired. What ever you do, do NOT purchase the model TPM-250 as it is obsolete and replacement parts are NOT available (learned the hard way). I heard Orange electronics also makes a pretty good unt for around $170. Perhaps some of the other forum members can comment on this if they have one.

I got mine from America's Tire company, and they were OUTSTANDING to work with. Understand that this unit goes inside the tire, so you have to break the bead to install it (it actually part of the valve stem assembly as is common with almost all the units out there). I did come across one that mounted on top of the valve stem, but was about an inch in diameter and looked pretty tacky on custom wheels. I've seen the red-yellow-green pencile tire pressure type you mentioned your friend has, but those require you to look at each tire. The type I installed is inside the vehicle and uses a radio transmitter. You cycle through and can see all the pressures including the spare tire if you buy and extra transmitter! It also alerts you if you get a slow leak while driving so you have time to pull over and deal with it. With low profile tires like my 45 series, you can hardly feel a flat tire until it starts coming apart!

Cheers,
Jerry