Abstract: A replaceable handle for side loading the proximal end of a medical device therein, which is typically inserted with the operating lumen of an endoscope. The replaceable handle can side-load the proximal end of the device into the handle for added manipulation of the distal end such as in removing a stone from the kidney or ureter leading therefrom. An inner housing is rotatable within an outer housing of the handle to secure the medical device in the housing passageway, and is spring biased to then move proximally with respect to the outer housing, moving the inner control rod of the medical device proximally to withdraw the stone basket mostly into the outer cannula and capture the stone for removal from the patient. A push button in the proximal end portion of the inner housing is depressible to permit insertion or withdrawal of the proximal end of the inner control rod of the stone retriever within the inner housing, and is releasable to secure the inner control rod in the handle.