The form of the wall units can be angular, straight (along the wall) or П-shaped. Before purchase it would be wise to measure your room and choose a wall unit according to your measurements. Usually wood, glass, metal and even plastic is used in production of wall units. Expensive and luxurious wall units are mainly made of natural woods, like oak and nut wood. There are also a lot of wall units basically made of flake board. However, as it is known, flake board can be harmful for the surrounding, so the salesmen should show you a certificate, which confirms the lack of harmful emissions. MDF is more ecological and more qualitative material and of course a little bit more expensive. The cost of a wall unit totally depends on the material, the quantity and types of modules the wall unit has.