The HLR21 has the 21mm orbit, marked 21 on top of the head in the picture, and is shown with a blue foam pad on its backing plate. The body is black with a carbon pattern, a blue pinstripe and the 18V battery at the back. The tighter orbit is the HLR15.
iBrid means the polisher runs from its battery or from the mains. The 18V, 5Ah lithium-ion battery gives up to 40 minutes at full power, as Rupes states it, and the dual charger tops up the battery with the higher voltage first so that one is always ready. Rupes lists a new eccentric set, a new anti-spinning ring, an in-runner brushless motor, new gear technology and an LED indicator.
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