Abstract: The present disclosure, in its various aspects, is directed to instrument accessory devices, implementation methods, and related delivery systems. Embodiments according to the present disclosure, including as described herein, may increase the effectiveness and efficiency of colonoscopy procedures, such as the removal of polyps. In one example, an embodiment includes an instrument accessory device with an expandable member, the device configured to receive an instrument through an instrument lumen, wherein the inner surface of the expandable member comprises a material characterized by a first elasticity and the outer surface of the expandable member comprises a material characterized by a second elasticity, the second elasticity being more elastic than the first elasticity.