I added a WiFi enabled Arduino board to my Mazzer Super jolly, to have a super precise timer that I can control from my phone. Still needs a bit of dialing in,
Mazzer Super Jolly w/ Timer Switch Commercial Espresso Grinder - Black
Mazzer Super Jolly Coffee Grinder with Timer for sale online | eBay
Mazzer Super Jolly Doser Grinder with Timer
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Mazzer Mini Timer Espresso Grinder Doser 58mm Burrs – Voltage Coffee Supply™