I think its marketed as a 300BLK kit because that cartridge has widely known issues in a Savage chamber, and folks shooting that specific round might be interested in something to fix what ails them.
I ordered mine via email with Lisa, and while even that was a PITA that parts eventually showed up.
I bought 3 and have only stalled one so far, in my long action 223AI and it improved things IMMENSELY.
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