This standard specifies the main dimensions and specifications of M10×1 flat-seat spark plugs and their cylinder head mounting holes used in power supply spark ignition engines.
GB/T 6784-1999 history
2012GB/T 6791-2012 Road vehicles.Spark-plugs and their cylinder head housing.Basic characteristics and dimensions
1999GB/T 6784-1999 M10×1spark-plugs with flat seating and their cylinder head housing
GB/T 6784-1999 M10×1spark-plugs with flat seating and their cylinder head housing was changed to GB/T 6791-2012 Road vehicles.Spark-plugs and their cylinder head housing.Basic characteristics and dimensions.