Wheel casters have become an important part of the everyday lives for most people. Although many aren’t aware of what casters are, these useful products are used in a variety of applications. From mechanic shops, trolleys, garbage bins, office chairs, to heavy industrial equipment, once you begin noticing casters, you are likely to find them appearing everywhere. So, what are casters? It is a wheel set in a metal shelter (including a plate of solo bolt opening for connection using screws), which is used to rotate 360o (granting the ability to move in all directions) or just move in...