Abstract: This base consists of at least two bars which are substantially parallelepipedal in section, each having an upper web and a lower web forming, respectively, the upper surface and lower surface of the bar and each fitted with at least one castor. Each bar also has an intermediate web parallel to the upper and lower webs and situated between them and having for each castor a portion cut away to accommodate the castor, each of these castors being attached to the said intermediate web. Application to the manufacture of furniture such as trolleys, chairs and the like and movable equipment for supporting objects.