The following wording may be used as a guide:

‘I bequeath, free of all duties the residue or (percentage) % of the residue of my estate; or the sum of $(amount); or (specified items) to WaterAid Australia (ABN 99 700 687 141), in aid of that charity and for its general purposes, with the written acknowledgement of WaterAid Australia to be accepted by my executors as a full and complete discharge.’