6.35 mm is 1/4" inch and I heard that is not for our cars. I assumed 6 mm. from another website, but I'll throw a "mic" (pronounced "mike" ) on a line tonight and let you know what I get. I'll bet AVL will get back to you with the exact answer for Mercedes as I thought it's a German company. Dieselmota (something like that) is a guy (on some BBS's and on eBay) who imports a lot of German stuff, including AVL stuff. He'd know the size.

Edit (later that evening) I measured 5.95 mm., so I assume the 6.0 mm. is the one to buy?

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The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)