An endoscopic stone-extraction device is provided comprising a support filament (910) comprising an end portion, a sheath (930) comprising a lumen (940), wherein the support filament (910) is disposed in the lumen (940) such that the sheath (930) is slideable with respect to the support filament (910), and a handle comprising an actuator (1700). Movement of the actuator (1700) in a first direction retracts the sheath (930) and causes a shape to expand outside the lumen (940). Movement of the actuator (1700) in a second direction advances the sheath (930) and causes the shape to at least partially collapse inside the lumen (940). Other embodiments are provided, and any of these embodiments can be used alone or in combination.
