I realise this is a bit of a strange question, my S-i-l has a rental
property with a bath but no shower mixer, ie just two separate bath taps
and would like a shower but isn't allowed to change the taps.
Normally one of those rubber things would do but these are strange
shaped taps...

Now, what I was wondering...these taps have aerators that unscrew -
anyone seen anything that would screw into the taps that I could then
fabricate into some sort of adapter that I could screw a shower hose into?

Combi boiler so balanced H&C mains pressure water.

Lee