There are seven rounds to the supplemental draft, but they are conducted in a manner far different than the spring draft extravaganza. The draft order is determined by a weighted lottery. A "round" lasts 10 minutes, with teams emailing the league in each round if they want to participate and select a player. If two teams select the same player in the same round, the team with the higher priority as determined by the lottery gets the player -- and forfeits its selection in the corresponding round of the 2016 NFL Draft.
Of this year's eligble players, Battle is by far the most likely to see a team sacrifice one of its 2016 draft picks for his services.