How to Tell the difference between Dyson dc04 clutch and clutchless models?

The main an obvious difference is that there is not clutch assembly and control knob on the base of the hoover. The clutchless models are for carpets only whereas the clutch models are for all floor types.

The clutchless model although is for carpets only, can also clean other types of floor.. the only negative is the noise as the brush is always on unlike the clutch models.