it's really a mix of road and mtb gear. for the derailleurs, you won't see rapid rise style rear derailleurs or any of the weird top swing front derailleurs ... so it's really the typical road style high normal rear, bottom swing front, but with the range to do an 11-34 rear and a triple in the front. this stuff just happens to be labeled as mtb gear. for shifters, it's almost always road style--either sti or barends ... or maybe thumbies or downtube shifters. 135 mm rear hubs are also popular.