A part of SAM Viaduct System (SAM VS). You can easily find all parts by entering 'sam vs' in the search engine both in Surveyor and CMP. This particular element is for connecting a SAM VS viaduct/culvert/bridge to the FMA Bank from the old FMA line. V-SAM stands for 'fits a SAM viaduct while B-FMA means it fits the FMA Bank (from the old set in this case)