You know, so probably the biggest challenge and undersea and it's the one that really affects every single vehicle that's, that's out there, you know, it's its energy. You know, at the end of the day, the, you know, propulsion power, you know, has to has to overcome drag, and, you know, ocean, the water is 100 times more dense than air, and drag is directly proportional to the density of the medium that you're traveling through, right. So, you know, an air you really don't have much of a drag problem in water you you absolutely right. There's a reason that every US Navy submarine is powered by a nuclear reactor. So the and you're not by that you're probably never going to put a nuclear reactor on a small little vehicle, and certainly not an expendable one. But, you know, that energy problem is, it's, you know, it's a big deal. And how do you get, you know, unfortunately, you kind of look at the last, you know, 1020 years, there's been steady improvements in energy densities and battery technology, you know, electric car vehicles really driven a lot of that, and it certainly will drive it and continue to drive that. But, you know, that's a problem that sort of goes across the board. I've been involved with some new energy development programs over the years. You know, early on when I started Riptide actually linked up very closely with a company called open water power. It was an MIT spin out that had aluminum sea water battery, that was really tremendous potential for what that could have done. It was acquired a couple years after I got involved with them by one of the large defense primes again, and, you know, they have, you know, I think they, there was a lot of potential for the technology, but I don't think it still ever sort of crossed the finish line to what it really could have done. But, you know, certainly batteries are a known and understood technology and they continue to evolve. And, you know, every once in a while there's something you know, new anode, capability, new electrolyte, something that gives it a little bit bigger kick, and we're always sort of leaning into what's the what's next. And, you know, there's some things with solid state batteries are coming along that are of interest. You know, out of the graphene stuff, we seem to we monitor pretty closely but you know, it really it's an important area for the technology and where things go. You know, the other big challenge undersea is obviously the environment, you know, it's corrosive, it's hyper Escher you know, the there's a lot of push in Kurt in recent years for deeper, deeper and deeper things, you know, as the, as some things open up with the ocean from exploration side clearly because you know, the bulk of the oceans very deep, right? Yeah, reasonably shallow, easily accessible places along the coast continental shelf, but a lot of the oceans would rather deep and the Navy as a greater need to go there, we're putting, you know, oil exploration is driving deeper and deeper, as the near shore sites become, you know, start to tap out. But there's a lot of things there with, you know, as you get into vehicle designs, you know, at the end of the day, a uv is, what makes the UV is really sort of it goes slow, right? It's efficient, it's neutrally buoyant. So it has to displace its weight in water. So that kind of drives you to, you know, how much you can put in it, to offset the that, you know, water is not too dense at the end of the day, compared to some of your metals, obviously. So, you know, you really have to get high strength to weight materials. We've done a lot in pushing deep with, for instance, carbon fiber, you know, that clearly was a recent, you know, big thing in the news with the Titan submersible on the Titanic, tragic, tragic event that never should have happened. There are certainly limitations to those materials. And they unfortunately, people learn that with their lives.