Step 1:  If your faucet is a "pull out" style: 

Please ensure you can unscrew the aerator (see here) to expose the threads. 

Note: For faucets where you cannot unscrew the aerator with a wrench, an aerator removal tool may be necessary.

Step 2:  After you unscrew the aerator: 

Measure the diameter of that opening and order the right adapter below if needed. 

Note: We include the 24mm and 20.5mm adapters with the order, however, if your faucet has a deep thread, you may need to purchase this in the "Extra Long" version (item a. or c.) below.

a). 24.0mm (0.95" Diameter) Extra Long - ST

b). 21.5mm (0.85" Diameter) - JU

c). 20.5mm (0.80" Diameter) Extra Long

d). 19.0mm (0.75" Diameter)

e). 18.5mm (0.73" Diameter) - TJ

f).  16.5mm (0.65" Diameter) - TT

*If you happen to have such a faucet type where the aerator cannot be removed, you may then want to consider our Undercounter Model: ULTRA-UC which comes with it's own dedicated faucet; or if you still wish for the Countertop system, then another option is to change your kitchen faucet to one that has a removable aerator.

Our Diverter screws onto the adapter and redirects the water to the countertop filter on demand by a turn of the handle.