In the Marvel Cinematic Universe, one of the most well-developed characters is Tony Stark. From the first Iron Man film to Avengers: Endgame, audiences were treated to a character that began as selfish but evolved into a true hero. After his big sacrifice to defeat Thanos, it seemed like there was a void left in the MCU. But while Stark may be gone, his legacy lives on in his last traditional suit of armor.
When Tony emerged from captivity in his new armor, he knew his life had changed. At first, his only goal was to liberate the weapons he created from the sinister people who had taken them. However, as that mission concluded, he began to find a new purpose in protecting the world and the people he cared about most. While it's a noble cause, it wasn't one that he could do forever. So as a result, he created the Rescue armor, which allows him to achieve both goals at once.
The Mark 49, aka the Rescue armor, was Stark's last suit of armor he made traditionally before transitioning to nanotechnology. Unlike his dozens of other suits, this was designed for his wife, Pepper Potts, and doesn't have a primary focus on combat. Instead, the suit was designed for search and rescue operations that certain pieces of machinery can't achieve. However, the first time the suit is seen is in the fight against Thanos, allowing fans to see the suit operate without holding back.
When it comes to protecting the world, the suit offers capabilities that some of his other armors don't provide. For example, the suit has multiple energy displacer sentries that fire repulsor beams. While Pepper uses this for battle, it could also be used for fast excavation or even protection while Pepper's busy saving lives. The suit is also one of the most durable, even with its thinner plating. In a way, the suit acts like armor to protect Tony's "world" as she goes and protects others. So now, whenever Pepper goes out saving lives, Tony will also be there keeping her safe.
Tony's nanotech suits represent the pinnacle of his engineering skills. Not only can they fit within his arc reactor, but the suit can also withstand the energy output of the Infinity Stones. But even though this technology can withstand massive amounts of energy, the new suits don't have the same coverage as the Rescue armor. In Avengers: Infinity War, when Tony fought Thanos, the Mad Titan knocked off pieces of his armor with ease. While Tony could've replaced it with more nanotech, it left parts of his body exposed at that moment. With the Rescue armor, Pepper will always have coverage, and since the suit was able to take on situations like Thanos head-on, she will never have to worry about being exposed or putting herself in danger the way that Tony did.
Tony Stark may be gone, but there are still heroes that are willing to carry on his fight. However, in Pepper's case, she isn't trying to fight bad guys. Instead, her armor represents the legacy of a man who initially only cared for himself but ended up caring about everyone. The Mark 49 is not just Tony's last traditional armor; it's everything he stood for being worn by someone he was willing to die for.