It's an ultra-stable hardware MIDI-Masterclock generator & has a great knob to give you full control over the tempo of your performances.
The midiclock generates incredibly accurate MIDI Clock messages.
It has two DIN MIDI outputs to connect to your gear. The clock signal can be distributed to more than two slaves by using MIDI Thru and you can start and stop everything with a single button.
Simply attach all devices that have MIDI Clock slave capabilities: Sequencers, synthesizers, drummachines and software like 'Live' from Ableton.
How to actually set the current BPM depends on the operating mode:
While using 'Live' mode, the BPM change immediately by turning the knob. You can use this mode if you want to make smooth tempo changes in your performance and are aware, that every turn of the knob changes the BPM.
In the 'Normal' mode, the changed value must be confirmed with a single click of the knob. This mode is perfect if you want to set your tempo once and simply need a stable clock signal. Accidental turning of the knob doesn't affect your BPM.