PVC (Polyvinyl chloride) is extracted from the polymerization of vinyl chloride monomer. We can classify PVC into two large groups, rigid PVC and flexible PVC.

Rigid: used for the construction of tubes, pipes, containers, tool accessories, parts of parts, blinds, windows, etc.
Flexible: Corrugated tube, traffic signs as cones. irrigation hoses, curtains for refrigerators, footwear, medicine, etc.

This material begins to soften at 80 ° C and melt at 140 ° C. Thanks to these and other properties, PVC is a recyclable material.

Among the main characteristics of PVC we find:

• Different degree of hardness.
• Waterproof.
• It does not corrode.
• It is moldable if it is subjected to high temperatures.
• Good electrical insulator.
• It is a very resistant material.
• Stable and inert.
• Good mechanical and impact resistance.
• High resistance to abrasion.
• Strong and lightweight.
• Good thermal insulation.
• It is odorless, tasteless and harmless.

Nylon or nylon is a polymer of artificial origin that belongs to the group of polyamides, based on a composition of diamine and diacid chloride.
According to the amount of carbon atoms in the chains of the amine and chloride, it is indicated behind the name, for example, the most common nylon 6.6.

Nylon as it is a very elastic and resistant material is ideal for the textile industry, mainly used foror in the manufacture of stockings in the USA.
Its application was extended until today, where not only do we find nylon in the textile application, but its applications have varied, being able to find this material in utensils, and machinery.

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 ...