Also, I think almost everyone agrees twins are sexy
Only if they are of the opposite sex.
cab9379 said:
Oh so i dont have to
buy twins just one since i already have an extension cap right?
I think you might be confused.

(Or else I am.)
There's a couple of ways that you can go to get an 18650 battery into your Mini.
1 - Since you said you already have an extension cap (to use the 18490 battery) from Provape, all you need is to get 1 Provari Ring made by Tatroe to go with Provape's extension cap. Mini + Tatroe ring + Provape extension cap = 18650 battery.
http://www.cigtechs.com/Tatroe-Ring-Provari-_p_396.html
2 - If I understand correctly (I don't own one), the Twins extension is a telescoping one-piece battery extension ring which gives you the option to use either the 18490 and the 18650 batteries, depending upon how far you telescope the extension ring. This would be used with the default Mini battery cap.