This caboose was built by the SEABOARD COAST LINE RAILROAD and is classified M-8. It never served on the SEABOARD AIR LINE RAILROAD. The SAL 5700 class wide vision cabooses were built by International Car Co. were renumbered 05700 through 05760 on the SCL, classified M-7. The SCL M-8 class cabooses were numbered 01150 through 01195. The caboose in this picture is carrying SBD reporting marks denoting SEABOARD SYSTEM RAILROAD. When the SEABOARD SYSTEM was formed former SCL cabooses were renumbered by dropping the leading 0 and adding a 2 in front of the number, hence SBD 21178.