Features

Standard Raspberry Pi 40PIN GPIO extension header, supports Raspberry Pi series boards
Dual-core Arm Cortex M0+ processor, flexible clock running up to 133 MHz
Onboard PCF8523 RTC chip, provides precise RTC information
Onboard MP28167-A buck-boost DC chip for fast load transient response
Onboard user-defined button, can be used for Raspberry Pi start up, safely shutdown, or other customized function
Protection circuits such as: power supply anti-reverse, counter current proof, etc. ensures stable and safe operating
Voltage/current monitoring circuit, monitors the Raspberry Pi operating voltage and current in real time
Comes with complete resources and manual

Package include

1. Power Management HAT (B) x1
2. 2x20PIN female header x1
3. USB cable type A male port to Type C male port x1
4. Screws pack x1

Resources available: https://www.waveshare.com/wiki/Power_Management_HAT_(B)