Z-Flex 4" Universal Appliance Adapters for Takagi Tankless Water Heaters

There are 3 different 4" diameter universal appliance adapters that are manufactured by Z-Flex that will be required to adapt the 4" single wall stainless steel venting for the Takagi tankless water heaters.  There is a standard 4" universal appliance adapter, then there is a 4" universal appliance adapter with back flow preventer and then there is the 4" universal appliance adapter with back flow preventer and condensate drain.

Below are links for the 3 universal appliance adapters for the Takagi heaters:

4" Universal Adaptor: Takagi (2SVSNA04.5)
4" Universal Appliance Adaptor with Back-Flow Preventer (2ZVB04)
4" Universal Appliance Adaptor with Back-Flow Preventer & Condensation Drain (2SVBFDPA04)