The three-axle super-high-decker coaches in the Setra TopClass 400 line-up are offered in three lengths. The range includes the 12.30-metre S 415 HDH, the 13.20‑metre S 416 HDH and the 14-metre S 417 HDH. While the S 415 HDH was unveiled to coincide with the market launch in 2001, the S 416 HDH is the most recent addition to the TopClass 400 family. This economical version was presented in autumn 2003 - its body 99 centimetres longer than its earlier stablemate. This three-axle coach offers outstanding seat comfort, boasting 50 seats with 4-star spacing. The S 417 HDH comes with all conceivable comfort features, along with large luggage compartment capacity, to ensure a consummate touring experience. The coach is very popular especially in Turkey where touring coaches tend to be used on long-distance routes.

The S 415 HDH is fitted with a Mercedes-Benz OM 457 LA engine developing 315 kW (428 hp) and a GO 210 power-assisted manual transmission. The S 416 HDH develops a higher output of 335 kW (456 hp) from the same engine and comes with the ZF-AS Tronic automated 12-speed manual transmission. The rear end of the S 417 HDH accommodates the 370-kW (503-hp) Mercedes-Benz OM 502 LA engine with ZF-AS Tronic automated 12-speed manual transmission. All three test vehicles already meet the Euro 5 emissions standards due to come into force in autumn 2009.