Mcapline fitting will fit on. Have had the misfortune to use one of these and it is a PITA to fit up but it does work suprisingly, even the magneticly operated plug. Just watch when you have to bore the bath for the control some baths (Ideal, Sottini) will have a stepped support board under the rim and cause problems not giving a flat surface for the locknut if it is positioned near the corner of the bath.
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