What is the difference between these two TPMS systems.

mike brez wrote:

JoeH wrote:

rgatijnet1 wrote:
I had flow through sensors and never had any trouble with them. Airing up the tires was no more difficult than if they were not there. The advantage is that I could LOCK them in to position which discouraged theft of the $50 sensors.
The sensors that you have to remove to add air are either kept loose or you have to use an Allen wrench to loosen them each time you want to add air.

The TST's don't use an allen wrench-- there is a special wrench that grips the base of the sensor below the anti-theft collar that you use to remove it to add air. Takes the same amount of time as removing a standard valve cap.

X2 it's the same exact little tool to install or remove either style. There is no Allen key.
I have the standard 507 and removed the anti theft collars from all of sensors

You are right. My flow thru sensors used a common Allen wrench to lock them in place. With the other sensors, all you have to have is the SPECIAL wrench to remove the cap or remove the anti-theft collar.
I'll stick with my flow thru sensors that can be locked in place and need no SPECIAL wrench to just add air.