Universal 100mm Flue Kit - Caravan, Motorhome & Marine A must-have universal flue kit for safely channelling flue gases from gas water heaters in static caravans, motorhomes and boats. Works with pretty much any 100mm gas water heater - including Ferroli Eco 6, Morco and Innovita Primo 6 - and is built to last, weathering all sorts of conditions. 12-month guarantee included. Every gas water heater needs a proper, correctly-sized flue to vent its exhaust safely outside - and that's where the Universal 100mm Flue Kit comes in, providing a plug-in solution for the most common flue diameter for compact instantaneous gas water heaters in caravans, park homes, motorhomes and boats. At 100mm in diameter, its got the flexibility to work with loads of different water heaters - including Morco models and the Innovita Primo 6 - making it the perfect