When fitting a Flettner 2000 Ventilator to a vehicle that has a lining of plywood or other substantial material, you will need to use a Flettner 2000 adapter. The adapter has been designed to bridge a gap of up to 50mm (1.97”) between the inner lining and outer face of the vehicle. Made from high grade ABS plastic the Flettner 2000 adapter can be cut down to match the size required and is available from all of our main distributors. Fixings not supplied.