In structural engineering, a lattice or a lattice truss of straight bars interconnected flat triangles forming knots (in flat trusses) or three-dimensional pyramids (in spatial lattices). In many countries they are known as armor or crosslinked. The interest of such structures is that the bars are working predominantly compressive and tensile presenting comparatively small deflections. Heterm is borrowed from traditional architectural lattice.

Depending on the need for installation and type of base, trolley or chair, we can find various types of fixation. Among the most common we find:

A - Through hole: It has a hole in which a screw or stem is inserted. It is a very simple installation system. Ideal for wheels that should not support a lot of load.
B - Threaded stem: It has a threaded stem or nut, it is fixed to the surface with a nut. It is usually the most used fastening system.
C - Angular plate: They are usually less used fastening systems, they have lateral plates to fix on the base.
D - Plate: It has a rectangular or square plate on its surface, it includes 4 or more fastening holes to the base, it is one of the most common.
E - Smooth stem: The stem without thread is inserted into the female of the base, we can find it in the typical office chairs with wheels, TV furniture etc ...