This module is based on the MAX7219 chip which is a compact, serial input common-cathode driver that interfaces microcontrollers to LED matrices. All common microcontrollers can be connected to this module by using a 4-wire serial interface. Each output can be addressed without refreshing the entire display. This module requires only 3 I/O lines for driving the display, making it ideal for your microcontroller projects.
 
Features
1. The single module can drive a 8 * 8 common cathode lattice
2. The module voltage: DC 4.7V~5.3V
3. Module Size: Length 3.2 X width 3.2 X height 1.3 
4. with 4 fixing screw holes, diameter 3mm
5. module with input and output interfaces, support for cascading multiple modules
6. Operating Current: 320mA