This is a brand new heavy metal armor based on Kellogg's arm brace. It can be obtained by getting it from a footlocker in the back of Kellogg's boss room along with a recipe for crafting it at the Chemistry Station.

The crafting recipe should be in your inventory when you try to craft the armor. It will be in the utilities section of the Chem Station and if it doesn't show up, try equipping the recipe item in the misc section of your inventory. Trying to equip it could be considered as reading it I guess.

I've been getting some reports that the damage resistances are weird for one tester and normal for the other tester but I think I've fixed it.

It works with whatever retexture you use for Kellogg's armor. I'm using this one for the screenshots: https://www.nexusmods.com/fallout4/mods/1356

Bare metal retexture created by Elianora: https://www.nexusmods.com/fallout4/users/3231858

Screenshots are appreciated!