Optimus Prime power bank is Transformers for adults

Autobots fans, roll out! Hasbro teases an Optimus Prime battery pack that's more than meets the eye.

Optimus Prime would like to save both humanity and your smartphone's battery.

In case you're a self-conscious adult who needs a cover story for your desire to play with Transformers toys, Hasbro has your back. The toy company's Hascon convention and fan event is coming up in September, and according to io9, Hasbro will offer fans at the event a transforming Optimus Prime power bank for $50 (£38, AU$63). 

The 6500 mAh battery pack folds up into an anonymous gray block when it's in disguise. It takes 16 steps to open the block up into Optimus Prime, the leader of the human-friendly Autobots. 

Optimus Prime normally transforms into a semi truck, but this power bank guise is definitely handier for anyone with battery-hungry gadgets. The robot also sports a shield and LED light-up sword that plugs into the pack's USB port.

Hascon takes place in Providence, Rhode Island, starting on Sept. 8. Hasbro's other brands include My Little Pony, Monopoly and Magic the Gathering. A limited number of Optimus Prime power banks will be available after the convention through the company's online toy shop

The power pack powers the light-up sword.