Modern era safety structure used to provide protection to personnel while working on top of freight cars Personnel wear a harness and clip a safety line to a slider on the overhead rail Two styles of columns included Two types of foundations included Perfect setting for SceneMaster(TM) Trackside Workers (949-6201, sold separately) Measures: 3-1/4 x 19-13/16 x 2-13/16′ 8.3 x 50.3 x 7.1cm as shown. Perfect for use with other Cornerstone HO Transload Facility structures, vehicles and accessories, sold separately.