This 4" / 100mm long flexible uFL 2.4GHz antenna has approx 4DBi gain and a 50Ω impedance so it will work fantastically with just about any 2.4-2.5GHz wireless receiver/transmitter such as the Adafruit CC3000s!
Antenna comes with a uFL (a.k.a u.FL / IPX / IPEX) connector, so no more need for additional adapters to get your IoT cloud flying high!