Updated for TRS2004 & TRS2006, these British Railways cast speedboards with white numbers are appropriate for BR maps (layouts) set in the 1950's and 1960's. Because they are compatible with both TRS2004 and TRS2006, a multiple replacement of existing speedboards within a map can be made in TRS2004 using TrainzObjectz before importing the map into TRS2006 (where multiple replacements can not be made as far as I am aware).
They are a re-texturing of Rabid's (kuid:33572) Euro Track Pack BR speedboards. My thanks to him for his permission to re-texture and for sending me the original files.