When doing replacement or upgrading on 1991 - 2002 Infiniti G20, the bulb size guide is necessary for you to take the reference.  
High Beam and Low Beam Headlight 1999 - 2002 9003
1991 - 1996 9004
Front Fog Light 1991 - 1996 H3-55W
Back Up Light 1991 - 1996 1156
1999 - 2002 921
Brake 1991 - 1996 1157
1999 - 2002 7443
Dome Light 1991 - 1996 194
1999 - 2002 DE3175
Front Side Marker 1991 - 1996, 1999 - 2002 194
Front Turn Signal 1991 - 1996 1156NA
1999 - 2002 7440
License Plate 1991 - 1996, 1999 - 2002 168
Parking Light 1999 - 2002 168
1991 - 1996 194
Rear Side Marker 1991 - 1996, 1999 - 2002 194
Rear Turn Signal 1991 - 1996 1156
1999 - 2002 7440
Tail Light 1991 - 1996 1157
1999 - 2002 7443
Center High Mount Stop Light 1999 - 2002 7440
1991 - 1996 912
Courtesy 1991 - 1996 73
Trunk 1991 - 1996, 1999 - 2002 158

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