FYI the store price is $21 and then there is a $5 mail-in rebate (and there is a limit of 2). At least that is how the ad reads here in CA.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).