The Mobile Proton Torpedo Launcher-2a—also called the MPTL-2a—was a medium mobile proton torpedo launcher crawler artillery platform that could fire proton warheads from a nine-tubed launch assembly deployed from its armored shell. Used by the Rebel Alliance, the MPTL-2a was developed to counter serious design flaws being exploited by the Galactic Empire in its predecessor, the MPTL-L.