The study is a prospective, multicenter single-arm cohort. Patients with wide neck bifurcation aneurysms (WNBAs) have few choices for safe and effective endovascular treatment. In this study, all patients with qualifying WNBAs will be treated with the WEB. The primary effectiveness outcome of the study is the likelihood of complete intracranial aneurysm occlusion on the 1 year angiogram as adjudicated by a core laboratory.