Some questionable claims made there. 2 Millionths of an inch tolerance and GAPPING a GLOW Plug??? No sign of any Machinery capable of the accuracy Claims Made either. Grinding and Lapping get those Fits. Cox's small engine sizes might have also Played a Part in Loss of Market. They weren't especially High Quality either.. The crankcases were Made from an extruded aluminium section, Not a casting. All designed for Mass Production and Low cost. Nev