The Pure Tone digital metronome has a range of 30 to 250 beats per minute. You can select different beats and rhythms, and the unit features a small speaker that plays a higher tone on the first beat of each bar to help keep you in time. The volume can be adjusted to suit, and using the included clip you can attach this to a stand or the end of an instrument.
Also features a clock and triplet rhythms.
The dimensions are 5 x 7.5 x 10 cm.