Bona door in Perfectline system are available in two types: opened to the inside and opened to the outside. Bona doors are characterised by  excellent resistance to atmospheric factors owing to use of PVC profiles they do not require any maintenance (painting) and will serve for long years. The door frame is made of a 5-chamber profile and its wing of a 3-chamber profile. The threshold structure guarantees thermal insulation in the bottom part of the structure and double seals decrease heat losses and eliminate draughts. The flexible cover profile covers assembly dowels. Steel reinforcement of profiles ensure optimum stability of the door. A drip cap drains driving rain water at wings opened to the inside and it serves as a decoration at wings opened to the outside. Bona door in Perfectline system are equipped with Winkhaus renowned fittings.