M16 (108mm L, Tamper Proof): Used for Audi TT clutch and belly pan, various Audi / VW transmission drain plugs, 2003 and later VW Touareg / Porsche Cayenne brake caliper bolts, Detroit Diesel’s flywheel bolts and front crank pullers on 900 and 4000 engine plus head bolts on 900 engine.
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