[Q] i need this hardware addon for nexus 4

anyone knows if this hardware really exists??
http://www.youtube.com/watch?v=gePKywB-VGI
and if it really works for nexus 4?

or if theres an alternative for that hardware?
i found this one..but looks it works for nexus 7
but i doubt it works for nexus 4
i hope someone can help me
https://www.youtube.com/watch?v=PO1nobiheDU