"I got the LED lights for my lego cargo train #7939. Lego should make red LED lights for the back of train pros: bright with new batteries. doesn't run batteries out that much Quicker. cool at night time.
cons: when batteries are low lights flicker and are not bright. if you put red studs on the lights they look slightly brown/orange. inside of cargo train is now a bit crammed.
over all they are good for the front of the cargo train"