The Doulton Duo housing kit is a cost-effective and easy to use filter housing unit manufactured from food grade plastic.
Head features 3/8" push fit connections and system includes a 10" long x 2" diameter short mount W9123006 Ultracarb ceramic filter candle along with a Fluoride 10" x 2" filter - W9125030 , mounting bracket and screws.
Replacement filters can be found here