Automatically close ads on youtube videos after an amount of seconds (default to 5 seconds). You can change the seconds on the settings page of the extension (chrome://extensions)
But why not just use a normal ad-block?
An ad-block completly removes all sorts of ads on youtube, making the video creator not get any money with monetization. This extension allow you to set a minimum time in which the ad will be displayed, and after that time, the ad will be closed automatically, allowing the content creator to get monetization on the video.