Add an isolation switch on-top of the Meter isolation switch?

[puddn_joint]

In my property I currently have one of these meters that has an isolator switch (use a flathead screwdriver to turn on/off)

I would like to add a Lewden enclosure with 100A isolator switch between this and the CU. Is this overkill and/or would cause confusion?

The reason I thought is that the screw turn seems a bit flimsy and is already a bit chewed up. Also in the future if a new meter is installed that doesn't have an isolator

 

[SJD]

Quite likely a future meter (like the smart meter you will eventually be given) won't include any isolator. So long as properly installed, I don't see any problem with having a second isolator that belongs to you rather than the supplier.