Gunson Colortune G4055B 12mm Classic Engine Petrol Diagnostic Adaptor Kit.
Brand new Gunson Colortune 12mm adaptor kit, allows the 14mm colortune plug in my eBay shop (search G4074 in my ebay store) to be used in 12mm plug holes.
Kit contains 12mm thread adaptor and gas seal washer. No hex key is supplied with this kit.
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