A slot car (sometimes, slotcar or track car) is a powered miniature auto or other vehicle that is guided by a groove or slot in the track on which it runs. A pin or blade extends from the bottom of the car into the slot. Though some slot cars are used to model highway traffic on scenic layouts, the great majority are used in the competitive hobby o

Mail receptacles or door slots are not required at businesses and offices that are open and have someone on hand to receive the mail when the carrier calls.

There are three common slotcar scales (sizes): 1:24 scale, 1:32 scale, and so-called HO size (1:87 to 1:64 scale). These are also commonly written as 1/24, 1/32, 1/87 and 1/64. Usual pronunciation is "one twenty-fourth", "one thirty-second", and so on, but sometimes "one to twenty-four", "one to thirty-two".