Variable length vascular occlusion system

A vascular occlusion system may include a microcatheter configured to navigate a vasculature, an elongate shaft slidably disposed within a lumen of the microcatheter, the elongate shaft having a lumen extending from a proximal end of the elongate shaft to a distal end of the elongate shaft, a plurality of occlusive medical devices releasably connected to the elongate shaft, and a release wire slidably disposed within the elongate shaft and at least a portion of each of the plurality of occlusive medical devices. The release wire secures each of the plurality of occlusive medical devices to the distal end of the elongate shaft when the release wire is disposed within at least a portion of each of the plurality of occlusive medical devices.