DOMETIC HEKI MINI - HEKI S Rooflight 400 x 400 with Ventilation for roof thickness 23-42. Suitable for Caravans Only with Forced ventilation. Featuring an easily adjustable fly net and blind for ultimate shading and pest control, the Dometic Seitz Heki Style roof light provides great thermal insulation and protection from the elements thanks to its proven Duette Honeycomb system.