H7 rings a bell...there's some info buried in the forum somewhere.
Edit...I'm an eeedjiot..D2S low beam....Just found these cool reference lists here:
http://www.sylvania.com/ConsumerProd...de/default.htm
2008 MAZDA 3 (With halogen capsule headlamps)
Low beam headlamp
H7
H7SU Silverstar ULTRA for Ultra Night Vision - The Whitest and Brightest Halogen
H7ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
H7EB EcoBright - Your Environmental Choice
H7XV XtraVision Halogen - The Brighter Light
H7CB Cool Blue Halogen - The Whiter Light
High beam headlamp
9005
9005SU Silverstar ULTRA for Ultra Night Vision - The Whitest and Brightest Halogen
9005ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
9005EB EcoBright - Your Environmental Choice
9005XV XtraVision Halogen - The Brighter Light
9005CB Cool Blue Halogen - The Whiter Light
Parking light
1157A
1157AST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
1157ALL Long Life Upgrade: Up to twice the life of the standard lamp
Front turn signal
1157A
1157AST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
1157ALL Long Life Upgrade: Up to twice the life of the standard lamp
Rear turn signal
7440
7440ST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
7440LL Long Life Upgrade: Up to twice the life of the standard lamp
992 (7440A)
Tail light
7443
LED
Stop light
7443
LED
High mount stop light
921
921ST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
921LL Long Life Upgrade: Up to twice the life of the standard lamp
LED
Fog/Driving light
9006
9006SU Silverstar ULTRA for Ultra Night Vision - The Whitest and Brightest Halogen
9006ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
9006EB EcoBright - Your Environmental Choice
9006XV XtraVision Halogen - The Brighter Light
9006CB Cool Blue Halogen - The Whiter Light
H11
H11ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
H11XV XtraVision Halogen - The Brighter Light
License plate
2825
2825LL Long Life Upgrade: Up to twice the life of the standard lamp
Back up light
7440
7440ST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
7440LL Long Life Upgrade: Up to twice the life of the standard lamp
Front sidemarker
1157A
1157AST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
1157ALL Long Life Upgrade: Up to twice the life of the standard lamp
Map light
2825
2825LL Long Life Upgrade: Up to twice the life of the standard lamp
Dome light
DE3175
DE3175LL Long Life Upgrade: Up to twice the life of the standard lamp
7443LL Long Life Upgrade: Up to twice the life of the standard lamp
Trunk/Cargo area
2825
2825LL Long Life Upgrade: Up to twice the life of the standard lamp
DE3022
2008 MAZDA 3 (With HID (high intensity discharge) headlamps)
Low beam headlamp
HID-D2S
High beam headlamp
9005
9005SU Silverstar ULTRA for Ultra Night Vision - The Whitest and Brightest Halogen
9005ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
9005EB EcoBright - Your Environmental Choice
9005XV XtraVision Halogen - The Brighter Light
9005CB Cool Blue Halogen - The Whiter Light
Parking light
1157A
1157AST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
1157ALL Long Life Upgrade: Up to twice the life of the standard lamp
Front turn signal
1157A
1157AST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
1157ALL Long Life Upgrade: Up to twice the life of the standard lamp
Rear turn signal
7440
7440ST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
7440LL Long Life Upgrade: Up to twice the life of the standard lamp
992 (7440A)
Tail light
7443
LED
Stop light
7443
LED
High mount stop light
921
921ST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
921LL Long Life Upgrade: Up to twice the life of the standard lamp
LED
Fog/Driving light
9006
9006SU Silverstar ULTRA for Ultra Night Vision - The Whitest and Brightest Halogen
9006ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
9006EB EcoBright - Your Environmental Choice
9006XV XtraVision Halogen - The Brighter Light
9006CB Cool Blue Halogen - The Whiter Light
H11
H11ST Silverstar High Performance Lighting: The Whiter and Brighter Halogen
H11XV XtraVision Halogen - The Brighter Light
License plate
2825
2825LL Long Life Upgrade: Up to twice the life of the standard lamp
Back up light
7440
7440ST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
7440LL Long Life Upgrade: Up to twice the life of the standard lamp
Front sidemarker
1157A
1157AST Silverstar Signal Lighting: Complete the Look: Crisp, Clean, Style
1157ALL Long Life Upgrade: Up to twice the life of the standard lamp
Map light
2825
2825LL Long Life Upgrade: Up to twice the life of the standard lamp
Dome light
DE3175
DE3175LL Long Life Upgrade: Up to twice the life of the standard lamp
7443LL Long Life Upgrade: Up to twice the life of the standard lamp
Trunk/Cargo area
2825
2825LL Long Life Upgrade: Up to twice the life of the standard lamp
DE3022