Those other super bright, super high powered tail light bulbs may be easy to see, but they also generate enough heat to discolor your lens and burn the paint.
Halogen bulbs are brighter than standard bulbs, but use less energy, which means they burn cooler. 12 volt only.
This bulb is shorter than a 1156 bulb and measures only 1-3/4" from bottom to end of the tip. From the pin to tip is 1-1/2".