How to get this Quality Selector button?

watchcartoonweb_com/_old-tom-episode-15 (Remove the _)




The quality selector just changes the video from VideoJS


By default it's 360p link video
If you click the 720p in the quality selector it just changes the video link to a 720p version of the video

Start here: http://www.w3schools.com/jsref/event_onchange.asp
That particular site uses the value of selected item as replacement url for the video source.
Also, site is using videoJS so there may be something to reference in their docs as well.

yes I meant VideoJS sorry, and I don't know anything about scripts I just want to add it to my website