"Videos of tests conducted in the swimming pool of Palisades Charter High School, about 20 miles from SpaceX headquarters, showed divers towing the pod through the water, lifting it out and depressurizing it. An engineer who had been riding inside then emerged from the tight space. He appeared to have just enough room to fit while lying down with his arms folded over his chest.Elon Musk Defends Mini Submarine Left Unused in Thai Cave Rescue -- Bloomberg
The aluminum pod followed earlier rescue ideas Musk suggested, including using an inflatable tube or air sock, and another type of pod made from Kevlar. Musk tweeted on Monday that the pod was “ready if needed” and that he would leave it in Thailand “in case it may be useful in the future.” With some modifications, the project could come in handy on a future rocket mission, Musk wrote. “This could also work as an escape pod in space.”"