These bulbs are “icy blue.” The blue color of the glass is intended to remove the yellow tint seen in clear bulbs. It is not a “Euro blue” color light.

The 9006XS bulb can be identified by the two prong plug, which points straight down from the bulb. There is a single bump in the plastic housing, between the two prongs.

A 9006 (non-XS) bulb bends at a 90-degree angle, making this style incompatible with a 9006xs.

Additionally, a 9005XS can be distinguished from a 9006XS by the two bumps in the plastic housing, located between the two prongs.