There are two versions of the concentric flue kit: One is fitted with either a 5 or 6 slot stainless steel terminal, and the other version (latest design) is fitted with a plastic terminal.
On the stainless steel version the terminal is secured to the inner 60mm tube only by means of rivets, these also secure the plastic air baffle in place.
On the plastic terminal both the 60mm and 100mm tubes are secured by three plastic tabs which locate into holes in the tubes. In the case of the plastic terminal the air baffle is incorporated into the design.
TEST REPORTS: Kit with stainless steel terminal: Gastec and Gaz de France Kit with plastic terminal: Gastec