What type camper do you have? Did you put it on all truck tires as well as camper? Thanks
Camper? Truck tires? Guess I forgot to say that it's on my 38' DP motorhome, AND on my 2115 Jeep Wrangler. Although the Jeep has its own built-in TPMS, it doesn't tell me in the MH cab, so I use some of the sensors for that. The TST system will work on most any tire with a schrader valve (normal car tire valve), and can handle at least a semi tractor and two trailers (maybe more, now). The package deal I originally bought included the monitor and 6 tire sensors, but you can buy these all separately if you wish.
And Mark, the TST 507 sensors are always on, update their readings internally every 12 seconds and, with no alarm condition will transmit the current state every 5 minutes, but alarm condition is xmitted immediately. The new sensors use 2032 batteries, while my old ones used a 1632.
The new color monitor I bought works essentially the same as the old one (smaller, monochrome, poor mounting, and is on whenever it is plugged in to DC power, or so long as you have the switch on when it's on its batteries. The monitor also comes with a nice suction cup mount for use on windows and a soft rubber (probably plastic, really) cradle mount for the top of the dash. Both work well.