This is a book inspired invisibility cloak/cape and it is NOT officially licensed merchandise as it’s not normally available to Muggles.
A quote from ‘Harry Potter and the Sorcerer’s/Philosopher’s Stone’:
“Something fluid and silvery gray went slithering to the floor where it lay in gleaming folds. Ron gasped.
“I’ve heard of those,” he said in a hushed voice, dropping the box of Every Flavor Beans he’d gotten from Hermione. “If that’s what I think it is — they’re really rare, and really valuable.”
“What is it?”
Harry picked the shining, silvery cloth off the floor. It was strange to the touch, like water woven into material.
“It’s an Invisibility Cloak,” said Ron, a look of awe on his face. “I’m sure it is — try it on.”
The cloak features a light, silvery fabric with a hood, finished with a professional hem. Please provide your height measurement during checkout to enable the length to be customised for you. The clasp option features a ‘Deathly Hallows’ style design.