A pair of Optare Solos parked up at Exeter Coach Station. On the left is MX55WDJ, an M850SL operated by Country Bus; on the right is WJ55FHD, a regular M850. The difference between the two models is that the SL has a narrower 'slimline' body - as can be seen by the way the rear wheels require a small mudguard extended out from the body.