For taps 21mm & 23mm, (13/16-Inch & 15/16-Inch) both male & female

To fit 21mm female flow diverter

How to measure: 
Firstly unscrew your aerator from the bottom of your kitchen tap.

Now measure the diameter of your aerator:
-If the aerator is a male thread measure the diameter from the outside of the thread.
-If the aerator is a female thread measure the diameter on the inside of the thread.
If this measurement is 15 mm then purchase the same thread adapter as your aerator thread.

Click here for photos and more information on how to measure your tap.