Tulderhof created a bigger version of the Twin, named the Tunnel- Twin. This is a relatively cheap solution to create extra inlet capacity in the front of a poultry house.

Tunnel-Twin air inlets are mainly placed in groups of 2, 4 or 6 inlets. This way, big openings are created which make sure there will be a good chilling effect during maximum ventilation.

The Tunnel-Twin is insulated with special foam, just like his little brother the Twin, and therefore it is well insulated and draught free. This is extra important for these big inlets, since they are not used in wintertime.

Click here for a project with Tunnel-Twin.