One embodiment is an apparatus for holding a device that includes a body having at least one aperture bounded by edges between a top and a bottom surface and having a holding portion wherein: (a) a first and a second resilient prong extend into the aperture, each prong has a movable end extending beyond the holding portion and having an actuating surface thereon; (b) the first and the second resilient prongs are disposed to urge the device against aperture edges; (c) the actuating surfaces of the first and second prongs are juxtaposed; and (d) a movable cam is interposed between the actuating surfaces of the prongs.