It is a 3-chamber system intended for constructing external doors, windows and various types of shop windows. The 24 mm thermal divider used, made of polyamide enriched with multi-directional glass fibre, significantly improves the external chambers’ and internal profiles’ mechanical durability. The thermal divider has been additionally equipped with a Coex sealing string that during the process of burning powder-coated profiles creates reliable vapour insulation and excellent sealing. The IMPERIAL door profiles have a thermal transmittance factor of UR=2,2÷2,3 W/m2K which classifies them in the 2.1 wg DIN 4108 material category. Owing to specific parameters: large profile width of 65 mm (window and door frames, pillars, door sashes) and 74 mm (window sashes), and a wall thickness of 1.7÷2.0 mm, a rigid, solid profile has been created that enables constructing doors with the maximum sash dimensions: 1300 mm width – with the maximum height of 2200 mm, 1200 mm width – with the maximum height of 2400 mm. The insertion fitting system: from 4 to 51 mm (allowing also for glazing from the outside), applying branded fittings and a wide range of doorstep solutions makes the system very universal and modern. An advantage of IMPERIAL windows is the possibility of correctly matching the sash to the window’s dimensions (several types of window frames and sashes) and choosing a sash suitable for the fittings – the offer includes sashes intended for typical aluminium fittings compliant with the EURO standards as well as PVC window fittings.