looking at. >> what is that? >> they are sort of like large doughnuts that grip the drill bit or the drill pipe when you're drilling it's the way we control, it's called the angular preventers. we use them when we do normal drilling processes so they can replace them when they wear out. they may have been worn out a little bit during some of the critical tests. they want to look at that. they will also be looking at all the hydraulic lines, accumulators that forced the rams closed and a lot of the mechanical parts of that nature and then they will be looking at the control panels in great detail, there's two control panels up in the lower marine riser package, the upper part of the blowout preventer. >> the science is one thing trying to figure out what happened but the other part of this story is this thing is now in the possession of the department of justice, the fbi