M SORA is a company with project approach which means that each customer is an individual chapter. Windows M SORA OPTIMO represent the latest line of timber and wood-aluminium windows of the company M SORA. Production of 5 models of timber and 2 models of wood-aluminium windows started in 2014 and windows are manufactured with completely new computer controlled machine. Timber windows - NATURE OPTIMO / L / X / XL - are made of spruce wood, whereas passive window NATURE OPTIMO XLT is made of thermally modified spruce and is the winner of the international competition "Component Award 2014", organised by the world's leading institute for passive buildings Passivhaus Institut (PHI) from Darmstadt Germany, for the most cost-effective passive timber window. Wood-aluminum windows - COMFORT OPTIMO L and XL - are also made of spruce and both models have standardly aligned outer aluminium cover on the frame and casement. All windows can also be produced from other wood species (e.g. larch, oak ...). Symbols L, X and XL in the names of specific model represent aligned frame and casement surface on the outer (L - "Line"), inner (X - "Xclusive") or both sides of window profiles (XL). All this illustrates the attractive appearance of windows and showings company´s up-to-date state with modern trends of building´s joinery design. Installation thickness of windows NATURE OPTIMO ranges from 92 mm to 110 mm, whereas the thicknesses of the windows COMFORT OPTIMO are 112 mm and 130 mm. Thermal transmittance of window NATURE OPTIMO is ranging down to 0.71 W/m2K and 0.66 W/m2K for model NATURE OPTIMO XLT, whereas thermal transmittance of windows COMFORT OPTIMO reaches 0.73 W/m2K. All windows have standardly built-in "warm edge" spacer and possess excellent air tightness, water tightness and resistance against wind load.