HISTORY OF
DENSO SPARK PLUG
●
1959
P2 plug
1962
P3 plug
1970
Wide plug
1972
G plug
1973
Resistor plug
HISTORY
1959 - 1974
Technology Development - Issues
1975
GU plug
3-electrode plug
Wide U Plug
1976
Double-electrode plug
1977
Semi-surface plug
1979
4-electrode plug
HISTORY
1975 - 1979
Company Background
Technology Development - Issues
Technology Development - Solutions
1981
Extended plug
1982
Small hex plug
Platinum plug
1983
ZU plug
1995
Double-electrode
Platinum plug
HISTORY
1980 - 1995
Company Background
Technology Development
Development After Launch
Technology Development
1997
Iridium plug
1998
IRIDIUM POWER
2003
Double needle
Iridium plug2008
TT plug
2018
Total production of
6 billion plugs
achieved