The Infantry Support Weapons is a Codex Entry featured in Battlefield 1. It is unlocked upon obtaining ten kills with the AT Rocket Gun.
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A CANNON THE SIZE OF A DOG[]
During the course of the war, a need for smaller portable guns that could engage strongpoints, bunkers and even vehicles grew. Sometimes these "mini-cannons" came equipped with a shield and their caliber could be as big as 37mm, which provided incredible power with armor penetration capabilities, but this came at the price of low mobility and cumbersome handling.