Endgame trailer have since revealed that the hoodie is based on the design of the team’s new suit, which many fans believe will help them travel in the Quantum Realm. However, they could be for ...

In the MCU, the Quantum Realm is a separate dimension. The main ways of accessing it (that we know of so far) are via Pym Particles (which power Ant-Man's suit) or via a Quantum Tunnel.

That title belongs to the rat that freed Scott Lang from the Quantum Realm in Avengers: Endgame. Without that roving rodent, Scott Lang would never have been able to get out of the Quantum Realm ...