A 5V power pack (or 5V power supply/power bank) delivers a regulated 5-volt direct current (DC) output to charge or power USB-compatible devices, single-board computers like Arduino, or small electronics.
 
A compact rechargeable build using a single 3.7V Li-ion cell paired with a 5V step-up (boost) converter and a TP4056 charging module.
 
It  has a Type-c connector for charging using the ordinally phone charges.  The output is a JST PH 2.54 2Pin Connector.