Pin fer: fer the for M5StampS3's 1.27mm pitch pin to the standard 2.54mm pitch for easy connection with other devices. Expansion interface: Provide 2.0mm 4pin Grove port for easy access to other M5 Unit modules. Control functions: Two tact switches for power and reset control for added flexibility. Convenient installation: Reserved fixing holes are convenient for fixed installation, suitable for application scenarios. High scalability: Provide users with options for expanded functionality and flexibility.<br><br>Compatibility: Compatible with for ecosystem for seamless integration with other M5 devices. Due to different batches, there may be differences in product appearance, color, and printed text, which not affect the use. Color:Black Material:PCB<br><br>Package Contents: 1 * expansion board kit<br><br>Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.