My stupid webcam doesn't do the color justice, but at least you get an idea.
It's not an "electric" purple...more of like a cornflower purple? If that's even possible. Either way, they felted in easily to my hair, the tips were almost automatically locked tight, and after the initial felting I haven't had to do a damn thing for them. I'd say they're roughly three inches long. Great for convenient pony tails without hair ties: