Dapol N 2P-009-601 BR RTC Test Coach Argus ex-Prototype HST MK3 Coach RTC Striped Livery

Following the completion of the HST development programme new uses were found for several of the Mk3 coaches built for the prototype train. Along with the two power cars restaurant buffet coach 40000 was converted by the Railway Technical Centre as a laboratory coach, Lab 15 Argus.
Later redesignated Test Car 4 this coach remans in operation, now part of the New Measurement Train.