Complex sentence: The Rainbow II is a rebadged Isuzu Erga Mio. It is most common available in non-step (low-floor) city buses and they have a rounded roof dome (more rounded than the Rainbow HR) with a double-curvature windscreen and a separate destination blind.
Split into simpler sentences: The Rainbow II is a rebadged Isuzu Erga Mio. It is most common available in non-step (low-floor) city buses. They have a rounded roof dome (more rounded than the Rainbow HR) and a separate destination blind.