The Rancilio Rocky coffee grinder is the perfect companion for domestic and semi-commercial espresso machine. It grinds directly into the group handle to ensure no stale coffee is stored or used. The Rancilio Rocky has a hopper capacity of 300g, flat 50mm grinding burrs and a burr speed of 1400rpm. Make sure you get the most out of your Merlo Coffee when you grind at home by following these three simple rules.