This is a driver carrier board based on the Texas Instruments DRV8825 chip. It is pin-compativle with the ubiquitous A4988 driver carrier board, but it's capable of more current (2.2 A with adequate cooling) and can take a higher supply voltage (up to 45 V). It also has up to 32x microstepping.
Please see the Pololu product page for more details, including schematics, adjustment instructions and warnings.
For optimum heat dissipation, you can assemble it with our long headers and stick a small heatsink on the underside of the board (tall headers and heatsinks not included).