Range is good and they set up very easily. The neodymium magnet is very strong so the reach is good as well, you don't need near contact to make them work. These are really designed for wood doors and windows. If you try anything else beware notes below. I had a few issues: Installation instructions say drill 7/8 hole. That is wrong! The unit is slightly over 13/64 so 7/8 is too large. Drill a 3/4 and file a little to make it fit. If you have retrofit windows installation will be difficult and maybe impossible. You need a pretty deep hole to install the transmitter. The old aluminum frame is in the way an you inevitably hit the edge of some part of the old frame so you can't just drill it out. Also, on the window side the depth may not be sufficient to hold the magnet shallower of the two parts. This too is a problem. Taken together installation with retrofit windows is VERY difficult.