BLACK-BOTTOM_V1.1 Universal Base M5Stack BLACK-BOTTOM_V1.1 Universal Base is designed for the Basic (Core) console. The M5Stack BLACK-BOTTOM_V1.1 includes a bottom battery switch for extended battery life, a built-in 110mAh lithium battery, and 2.54mm spaced pin headers. The device also has female headers for user expansion and embedded magnets for magnetic attachment in various situations.