The Mk6 Mercedez-Benz evolved from the last few vehicles of the Mk5 class when the former body builders Pressed Metal Corporation released the PMC160 body. While not originally being suited to route work the class was soon redeployed onto both Airport Express and Sydney Explorer routes. Following the cessation of the Airport Express a number of these vehicles have been sold and a few have returned to regular work whilst they still perform most of the Sydney Explorer services.