We (Blue Line Trailers) have had these trailer socket mounting plates specially laser cut from 3mm stainless steel.

Cheaper, thinner mounting plates can rust and can bend and break when you're plugging in your trailer, caravan or horsebox.
 

Easy to Fit

This mounting bracket features a slot where socket fits. This makes fitting  a new socket quick and easy without having to disconnect and reconnect the wiring.  

Fits Euro 13 pin socket