I'm sorry if I have misunderstood your question, but I just wondered what your motivation was for using a smaller tap?
Bath taps usually have a 3/4" threaded tail, whereas basin taps are 1/2" - and they may connect to 22mm and 15mm pipes, respectively.
So the type of connection you need, will depend on your pipework, and the tap you go for.
If you did want a basin tap on a bath, you may have issues with the flow rate.
You will also have to find a way to mount the smaller tap tail in a larger hole, and seal the remaining gap appropriately.
It may be simpler to try and find smaller bath taps!
@RandomGrinch Thanks for the reply.
I wanted to fit one of these:
that's this ebay item: ebay.co.uk/itm/234036784992
I measured the bath tap we've got and the aerator measures 1.25 inches.
Nothing I've seen for sale is the same size. The biggest I can find is 3/4 inch?
Will I be OK buying the above unit?
Thanks.
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