Sliding rear windows

What is there to use for protecting a truck rear sliding window. Say if some one open it the alarm would go off. I dont want a motion sensor. want some sort of instant trigger. Thanks Kyle

Reed switches (magnetic). They usually come with double sided tape so you can mount them on the frame of the window. Here is an example but the price is way to high here. Just cut off the screw tabs (if you want) and then tape the one with out the wires to the window (moving part) and the part with the wires to the stationary frame. Run one of the wires to either ground or positive depending on what trigger you have free in the alarm. p.s. Wondering, is it possible to drop a little wooden dowl in the track to keep them from opening or limiting the travel. Never really looked at them just thinking about how the do it in houses.

Ok here is the easy way from a long time installer(12 years)...Race down to the nearest Radio Shack and ask for the switch mentioned but they will call it a home door or window alarm contact and in florida it costs just 2.89 that will give you a sensor and then ground one of the wires and fun the other to the Instant negitave trigger or the hood pin wire on the alarm and your procted...                   Hope this helped