Bluetooth controllers like a DS4 on an NES?

I loaded up Amazon earlier and found a Bluetooth adapter for the NES that allows you to use Bluetooth controllers. Never heard of it before and it seems to be temporarily out of stock. Any ideas?

https://www.amazon.com/gp/aw/d/B01D..._m=ATVPDKIKX0DER&pf_rd_r=698ER130W04D2MEHFEQJ

 

I saw an article on like gizmodo or something recently, probably why its sold out.

 

Play asia has it for sale

 

More information here : http://www.analogue.co/pages/8bitdo-x-analogue

 

It's a cool idea, and 20 bucks isn't a bad price. I may have to pick one up, I already have one of the 8bitdo's NES style controllers..

 

I have one controller too. And as you said, it is not so expensive !