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Up for trade is Salem Wiki: Rattler Serum.
How many times have you lost proficiency points after being knocked out by a timber rattler? Then on top of that losing all your Savage Charms in the middle of nowhere while you were on your way back to your settlement. Put an end to your worries by always carrying this serum. The serum has 10 uses and each use works just the same for 5 bites as it does for one so make sure that vile creature has met it's end before drinking up.
Edit: SOLD! Thank you for trading.