Crack open and slide doors are an alternative to standard balcony doors. If you want to save the space taken up while opening a balcony door wing, you can use the crack open and slide system. As the name suggests, the wing can be crack opened (as in standard balcony doors) or slid (depending on the need, either to left or right). Sliding doors also have this advantage over the ordinary balcony doors, that they do not shut by themselves due to strong wind or draft. Bertrand company offers such solutions in all technologies (PVC, wood, aluminium, wood-aluminium.) The colours, similarly like in the folding systems, can be selected according to the individual preferences of the user.