The Hydrotech 40600042 is the correct replacement for the following systems:
The Hydrotech 40600040 Flow Restrictor is a Reverse Osmosis Flow Restrictor that is used if you have a Hydrotech RO system that did not come with a 25 GPD Membrane. This part will enable you to put a 25 GPD membrane in your Reverse Osmosis system in order for it to function properly.
Hydrotech 40600040 25 GPD Flow Restrictor Specifications:
Upon replacing the flow control with the Hydrotech 33137 Retrofit Kit, this will allow the Hydrotech 40600040 Flow Restrictor to be used in the Hydrotech 101, 201, and 301 Series reverse osmosis systems and Hydrotech HT / HTF RO systems.