An on-board information system is provided, including a help facility, which is operable to provide information to a requester. Old melt is purged from a shooting pot having an injection plunger slidably received in an injection cylinder. The position of the object is variable depending on which aperture the snap fastener snaps into, with the user selecting where to locate the object by selecting the location at which the snap fastener connected thereto will engage with the compartment defining structure. The induced slight phase changes on the sensitive probe laser beam with reference to the phase reference laser beam are detected through differential phase interference contrast phenomenon so as to allow each of the tiny metal particles in the given medium to be imaged as an optical label. Moreover, the bumps are formed on the outer surface, and the height of each bump is different from each other. The associated frame portions also comprise attachments for supportedly connecting two wheels of the vehicle, a seat disposed on the frame, and other vehicle accessories and systems.