TVM Block Marker. This sign marks the limit of a block section on lines with TVM cab signalling.
Own work (i.e. SVG coded by uploaders), based upon: (in English) (October 2009)  Railway Group Standard GI/RT7033, Lineside Operational Safety Signs (PDF) (2nd ed.), London:  Rail Safety and Standards Board, p. 30: Sign AB04: TVM Block Marker Retrieved on 3 December 2012.
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