This USB to 5.5mm / 2.1mm DC Booster Cable integrates a boost converter allowing you to power 12V devices directly from any USB port such as a computer or a battery pack. It outputs a stable 12V DC voltage suitable for center-positive DC barrel jack powered devices with a 2.1mm opening and spring-loaded center terminal. The cable is rated for 500mA output, with tested capability up to 700mA with some voltage droop, but continuous current above 500mA is not recommended.

Key performance efficiency varies by current draw:

• 50mA draw: 12.4V output, 83% efficiency
• 100mA: 12.4V, 86% efficiency
• 200mA: 12.3V, 86% efficiency
• 300mA: 12.2V, 84% efficiency
• 500mA: 12.1V, 81% efficiency
• 700mA: 11.4V, 75% efficiency

The cable length is approximately 1.15 meters (45 inches) and it weighs about 34.6 grams. It provides a quiescent current of 3mA. Note that USB port voltage and cable quality may affect output performance.

This is a handy and efficient solution for powering 12V DC devices using standard USB power sources.