These are secondhand Phantom 2 batteries. They have been taken from faulty drones. Given the age of the batteries, they come with a 30 day warranty

This genuine DJI Intelligent Flight Battery is the 5200mAh version to fit the Vision+ and the Phantom 2.

It has quite a few impressive features:

1. Easy plug-in and removal

• Simple connectors and a cartridge design make inserting the battery and pulling it out super easy.

2. Precise Battery Level Indication

• Battery levels used to be estimated by measuring voltage. The DJI Intelligent Flight Battery monitors the total amount of energy consumed, so it can offer a precise battery level indication.

3. Super Long Flight Time

• While 25 minutes is typical, DJI have apparently flown a Phantom 2 Vision+ for 28 minutes!

4. Integrated Battery Level Checker

• Find out remaining battery levels whenever you want, just by pressing the main button on the battery front.

5. Much Easier to Recharge

• All balancing and protection circuits are integrated inside the battery, making charging as simple as connecting the battery to the charger. Battery indicator lights keep you updated on charge progress.

6. Safer than Ever

• Short circuit protection and large current protection are all integrated into the battery.

7. Increased Battery Life

• In the past, if a battery was dropped it might stop working. The DJI Intelligent Flight Battery’s frame protects the cells, keeping batteries safe.
• In the past, if the battery wasn’t disconnected, it would drain and become unusable. The DJI Intelligent Flight Battery has low voltage protection. Once it reaches a certain limit, it will turn itself off.