Indigo skins have a discernible feature; the top parts of the guns are painted in an indigo color. The rest, for instance; the magazines, the buttstock and the barrels are all in different, but similar and complementing hues. There are currently three skins in this family, which were added into the game at different times, during different updates. All of the skins come in all five exteriors, and two of them have the Souvenir option.
The price of Indigo skins barely exceeds $20.
Check out other CS:GO skins families: