[Help] How to make item affect saving throw bonus

Super simple question if anyone has the answer! So I have an item that gives me +1 to CON saves (it's a homebrew item) and I'm trying to add it to my character sheet. I just don't know how to give the item said attribute (like how you type "Strength: 1" in the "MODS" section for an item that boosts strength by 1). I've tried typing a few things that I thought it could be (i.e., "Constitution Save: 1", "con save: 1", "@{constitution_save_bonus}: 1") but nothing is working.  Sorry if that was hard to understand but hopefully it got my point across lol

According to this (likely out of date now sadly) list , you should have been on point with the 'Constitution Save: 1' option... maybe a casing issue? All of that said, I can't any mods beyond attribute boosts to work lol