Compression relief adapter
Fuel injection spark plug
Igniter plug structure having semicircular grooves
Ignition plug
Ignition plug for improving fuel economy of an internal combusti
Ignition plug with air passage and double check valve
Ignitor for liquid fuel rocket engines
Spark plug attachment
Spark plug with increased pressure resistance
Spark plug with pre-combustion chamber and venturi passage
Sparking plug with efficient air supplying system and a removabl