An In-video ad from ExoClick, served in pre-roll. You can find more info on how to set up ads with ExoClick in this guide - Using ExoClick Ads With FV Player.
This is an ad in the overlay box format. It's set to appear before the video starts, on pause and in post-roll.
In-Stream ad format is using the VAST video ad standard, therefore requires the FV Player VAST to be used. The ad won't load every time - that's due to the ad server settings. Read more in the ExoClick FAQ.