Windows offered by OKNOPLAST are appreciated by architects and are used in many house designs. Big glazed surfaces are an interesting solution and, therefore, the company strives to keep abreast of trends and meet the expectation of customers by offering several types of patio doors, including the HST lifting-sliding doors. Their special design enables creation of very large glazed surfaces with the maximum surface area of nearly 14 m2. The opening leaves can be 3 m wide and, despite their large size and significant weight, they open easily. Our offer is supplemented by the PSK and PSK-Z tilt-sliding door system and the PSK Atrium hoisted-sliding door system, patio windows, and balcony windows.