The Cost of Extending Systems IS Slichtly Higher than Ordinary One, and is Dependant, First of All, On the Volume and Material of the Door Leaf, Box and Platbands, And ALSO Unts on Which Its Strictly Impossible to Save. The more Weighty the Door Leaf, The Most Reliable Fastening and the Ringing for it will be needed, but it Meens that it is grows and the Price.