Chameleon skins are known for its unique appearance that features a large chameleon on the side of the weapon painted on the black base. Currently, the Chameleon skins family has only one member among its ranks, it being AUG | Chameleon which was introduced to the game during the Operation Phoenix Update back in February 2014. The skin is available in all five exteriors and can have the StatTrak technology attached to it. It is also a part of The Phoenix Collection and as such can be obtained by opening the Operation Phoenix Weapon Case with an appropriate key.
Check out other CS:GO skins families: