There are so many different types and sizes of pressure switches, that it can be hard to find a good replacement pressure switch for your air compressor.

It's often safest to buy a replacement pressure switch directly from your air compressor manufacturer. Or find the exact same make and model online. But that can often be very expensive, so people search online for a cheaper alternative.

So, what is important when looking for a (replacement) pressure switch, and what is not?  when buying a replacement pressure switch, you should keep in mind all of the things mentioned on that page.

Here is that list again, with a small explanation what to watch for.

Type of control buttons (off/auto buttons/switch or no switch)
Electrical connections and power rating (number of phases and power in kW or amperes)
Pressure range (highest/lowest possible pressure setting)
Mechanical connection (size of the pipe connection for compressed air)
Unloader connection (size/type)