Peanut Butter Mixer We love natural peanut butter! But not the way its oil separates to create a gooey unstirrable mess. This clever invention makes short work of that scenario. Just screw Grandpa Witmer's Natural Peanut Butter Mixer onto any standard 16 oz. peanut butter jar and crank its chrome-plated mixing rod. Oil is smoothly and effortlessly stirred back into your peanut butter. There s even a gasket that wipes the rod as you remove it and a removable lid liner that make clean-up a snap. No spills. No hassles. Just magically mixed PB in seconds! Made in the USA.