"Electric Blue" is kind of a misnomer with this color, as it's really more of a deep royal cobalt, but it's positively gorgeous and my absolute favorite blue hair dye ever. My hair is currently dyed this color, and I was walking around my apartment holding it up to various things so I could describe the actual color - the blue on the Reynolds Wrap aluminum foil box is probably the closest match. And I will say, the color positively EXPLODES in the sun! Like many of the SFX colors, it's not "flat" looking at all - it's shimmery, beautiful, and looks as natural as blue hair possibly can - in other words, it doesn't look at all like some sort of flat-colored costume wig.
Like most of the SFX colors, Electric Blue works best on top of bleached hair. The color is dark enough to show up just fine on hair that's been lightened to dark blonde or super light brown (the color that's kind of the border between brown and blonde), but if you try and put it on medium to dark brown hair, you'll start getting undesirable greenish tones that will fade to a weird dingy green after a few shampoos - so definitely bleach first unless you're a natural blonde. Also keep in mind, the lighter you bleach your hair, the more "true" and vibrant the color will be. The degree to which your hair is bleached also greatly impact how the color looks as it fades. If you started out with a brownish or yellowy color, Electric Blue will take on a green tone as it fades - this is pretty at first, but it will end up looking sort of chlorinated and weird once the majority of the color washes out (this is when it's time to re-dye!). If you started out with more of a super light ash blonde, the blue will get lighter and paler as it fades, which is also pretty at first, but it finally ends up as sort of an old lady frosted blue tint (also time to re-dye, unless you're dressing up as your grandma for Halloween). Electric Blue doesn't seem to have as much purple undertone in it as some of the other SFX blues, so it won't fade along the purple\pink spectrum, no matter what level of bleaching you started out with. Also like most SFX color, the life of the color can be extended by using a sulfate-free shampoo, washing your hair in luke-warm water rather than hot, and shampooing on alternating days instead of every day. Bottom line: this is one of the most breathtakingly beautiful hair colors I've ever seen or used, but you'll need to put some effort into the upkeep, since this one's end stage fade color isn't very desirable. It's completely, 100% worth the extra work though. I get tons of compliments on this color every time I leave the apartment.