Below you will find several different versions of our Digital Ferrous Metal Proximity sensor. The first choice, the 275VPD is our smallest and most commonly used version. It is factory programmable to trigger on any gap up to about .4". The other choices are all larger and very similar, with the difference being the magnet size. These larger magnet sensors can see targets up to a gap of about 1.4". Click on the box that best fits your needs, and you will be brought to the electrical option choice page.