apparatus for transportation and display of demonstrations and articles of merchandise utilizes a trailer part with undercarriage for facilitating movement from one location to another and is also provided with vertically adjustable castors which can be utilized to lift the carriage clear of a floor or road surface so that the vehicle can be maneuvered on the castors alone . in order to increase the area available for product display while maintaining dimensions more suitable for transport and , at the same time , providing protection for articles being transported , a box like body is provided on or integral with the trailer , the box having open sides covered by box - like covers each cover provided with , when closed , an inward facing open side , the covers each being connected by vertical hinge arrangements to a vertical corner of the body to allow horizontal swing - out - opening , the covers including , within themselves , display spaces which are visible when the covers are opened .