BMMO SOS 'SON' single-deck Bus 0 ▲ Home on Vintage Buses 4 hours ago · Life · hide · 0 comments This handsome well preserved bus, registration RC 7927 fleet number 417 is a 1940 BMMO SOS ‘SON’ single-deck bus originally built for Trent Motor Traction. No comments yet. Log in to reply on the Fediverse. Comments will appear here.