The M113 was developed by Food Machinery and Chemical Corporation (FMC), which had produced the earlier M59 and M75 Armored personnel carriers. The M113 bears a very strong resemblance to both of these earlier vehicles. The M75 was too heavy and expensive to be useful, as its weight precluded amphibious use and transport by air. The lightened M59 addressed both of these problems, but ended up with too little armor, and was unreliable as a result of efforts to reduce its cost.