Yellow Power rings are fueled by fear instead of willpower, but function the same as their green counterparts. Members of the Sinestro Corps are chosen for their ability to instill great fear in others. In order to become a member of the Sinestro Corps, one must free themselves from a small prison. With their yellow power ring completely drained of its energy, they must provide it with the spark it needs to accomplish this feat by facing their own greatest fear. Originally Yellow rings could be charged by Manhunter androids that have yellow power batteries built into themselves, which in turn are connected to the Central Yellow Power Battery on Qward. There are also portable batteries similar to those used by Green Lanterns. Aside from the recharging limitations common among the various Corps, their only known weakness is that their power can be drained by a Blue power ring or disrupted by a Red Power Ring