In some aspects, the present disclosure provides a delivery device for delivering a detachable medical implant that comprises an elongated delivery member and a first engagement portion. The first engagement portion comprises a first proximal-facing surface, a first distal-facing surface, and a first lumen that is configured to accommodate an activation wire, wherein at least 50% of a surface area of the first proximal-facing surface is angled away from a proximal end of the first engagement portion. In other aspects, the present disclosure provides a medical delivery system comprising: such a delivery device; an implantable device comprising a medical device portion and a second engagement portion, the second engagement portion comprising a second lumen configured to accommodate an activation wire, a second proximal-facing surface and a second distal-facing surface; and an activation wire. Other aspects pertain to methods of medical device delivery using such a medical delivery system.