This is for 1 pair of Green bulbs part number 921!!This is a direct replacement, no modifications are necessary!These bulbs will work in any 921 Applications like: Backup bulbs (1 pair, 2 bulbs are included)Turn Signal LightsParking LightsInterior LightsAnywhere you can put any 921/ 912 bulb!!These bulbs carry a full 1 year, no questions asked warranty