Quantity   Component name
1 × AAA to AA battery adaptor It's basically a plastic shell that allows you to use an AAA battery in place of an AA in a pinch
1 × LM7805 Power Management ICs / Linear Voltage Regulators and LDOs
1 × wire
2 × 14500 lithium cells 3.7v Lithium cells that are the same size as AA batteries
1 × 5v switching regulator