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