Based on the Allegro A4988 stepper driver chip, this board drives bi-polar stepper motors up to a max 2A/phase. It is a chopper microstepping driver which defaults to 16 step microstepping mode. It can take a maximum motor drive voltage of around 30V, and includes on-board 5V/3.3V regulation, so only one supply is necessary. Although this board should be able to run most systems without active cooling while operating at 1.4-1.7A/phase, a heatsink is required for loads approaching 2A/phase.
Spec sheet available in PDF format.