Avengers: Endgame concept art reveals an early design for the time travel suits. Five years following their devastating loss to Thanos (Josh Brolin) in Avengers: Infinity War, the surviving heroes banded together in the hopes of bringing back those who disintegrated into dust via the snap. This required them to travel back in time to collect all six Infinity Stones and create their very own Infinity Gauntlet. The trip called for new mechanics to make time travel possible, like the Quantum Suits worn by the Avengers.

Between Hank Pym's (Michael Douglas) Quantum Realm research and Tony Stark's (Robert Downey Jr.) wrist device that allowed them to visit certain points in the MCU's history, the team found themselves traveling back in time. This new mission called for time travel suits that helped them survive their deep dive into the Quantum Realm. Like Iron Man's armor, the suits are made of nano-tech, making it easier to get in and out of them. This was the first time that the Avengers got something as close to a uniform and they will forever be associated with Endgame. However, before directors Joe and Anthony Russo decided on the sleek looking, red and white costume, there was an early version of it the suits that looked very different.

Digital artist Aleksi Briclot shares a concept art he created for Endgame's Quantum Realm suits which is very different from what ended up on the big screen. For starters, it's colored yellow, not red and white. It's also much bulkier and it's headpiece is reminiscent of an astronaut's helmet. According to the creator, this was inspired "by elite pilot like those from Sr71, you know the Lockheed Blackbird also used by the Xmen."