Sno-Stuff introduces its new "Series 4" mini dollies. Made from high quality, extremely durable nylon composite, these new dollies are a step above other designs. Incorporating 4-360 degree dual wheel swivel casters, the Series 4 dollies are stable as it gets. A traction pad / centering device make bar location easy, effective, and maintains dolly grip even over tough surfaces. This really is the next generation of mini-dolly.