Features:

Automatically times every shot of espresso

Works with any home or commercial espresso machine using 24V AC, 120V, or 240V grouphead (3-way) solenoid valves

Installs in minutes without tools or modifications to the espresso machine

Guaranteed to work with the Linea Mini, Linea Classic EE and AV, Linea PB AV and ABR, GS3 AV, GB5, Strada AV EE and EP, Quick Mill Silvano, Rancilio Silvia, and Dalla Corte Mina

Incompatible with E61 group machines that use a manually actuated valve for brewing