Last week, SpaceX CEO Elon Musk revealed a photo of the main-body construction tool for the company BFR — the Big Falcon Rocket. The tool is analogous to the turning mandrel tool that Boeing uses as a rack for a 787 composite fuselage while it’s being built up from layers of carbon fiber.

A number of outlets, including Teslarati and GeekWire, have speculated that Ascent Aerospace’s Coast Composites division is behind the tooling. A spokeswoman on behalf of the company declined to comment when contacted by Composites Manufacturing.

Last month, Musk said the spaceship is already under construction and should be on track to start test flights next year. SpaceX’s tentative specs suggest the spaceship will be 30 feet in diameter and about 157 feet long. The craft is meant to accommodate about 100 people in 40 cabins when it’s configured for Mars trips. Musk said the first, unmanned BFR mission to Mars could take place as early as 2022.

In 2016, Musk showed off a large, composite fuel tank for the BFR that will contain pressurized liquid oxygen.  Musk revealed the tank would be “built with [the] latest and greatest carbon fiber prepreg” – carbon fiber that’s pre-impregnated with a resin to make it tougher. “In theory, it should hold cryogenic propellant without leaking and without a sealing linker,” he said. Carbon fiber’s high tensile strength, design flexibility and low density are also major benefits.

To learn more about the BFR, check out the video below.