A clamping mechanism for a holding device, the clamping mechanism comprising: - a hollow body having opposing first and second end openings; - a retaining device which is inserted into and/or at the first end opening of the hollow body; - a translatable component at least partially positioned in the hollow body; - the hollow body including various indents, protrusions or shoulders near the second end opening, said various indents, protrusions or shoulders being at least configured to limit the motion of the translatable component, the retaining device and the various indents, protrusions or shoulders cooperatively defining a region therebetween; - a hollow, rigid collet surrounding the translatable component such that the translatable component is hydraulically axially translatable relative to the collet, the collet having one or more sidewalls, a first open end, and a second open end, the collet having a plurality of slots formed through the one or more sidewalls, wherein the slots are circumferentially spaced around the one or more sidewalls of the collet and are vertically or angularly extending from at least one of the first open end, the second open end, and a point between the first open end and the second open end, the collet having a longitudinal length, the one or more sidewalls having a cylindrical outer surface the entirety of which is parallel to a central axis of the collet and an inner surface including a plurality of grooves for providing debris relief; and - a hollow sleeve positioned in the region between the retaining device and the various indents, protrusions or shoulders, and covering the collet, the sleeve having a first end and a second end opposite the first end of the sleeve, wherein the sleeve is radially flexible and configured to be radially actuated to press against the one or more sidewalls of the collet with sufficient force to flex portions of the collet to grip the translatable component, the sleeve having a longitudinal length less than the longitudinal length of the region between the retaining device and the various indents, protrusions or shoulders; - a first seal contacting the sleeve near the first end of the sleeve; - a second seal contacting the sleeve near the second end of the sleeve; - a preload ring positioned near and spaced from the second open end of the collet, the preload ring further being positioned between the hollow sleeve and the translatable component; and - a preload O-ring positioned between the preload ring and the collet. - a hollow body having opposing first and second end openings; - a retaining device which is inserted into and/or at the first end opening of the hollow body; - a translatable component at least partially positioned in the hollow body; - the hollow body including various indents, protrusions or shoulders near the second end opening, said various indents, protrusions or shoulders being at least configured to limit the motion of the translatable component, the retaining device and the various indents, protrusions or shoulders cooperatively defining a region therebetween; - a hollow, rigid collet surrounding the translatable component such that the translatable component is hydraulically axially translatable relative to the collet, the collet having one or more sidewalls, a first open end, and a second open end, the collet having a plurality of slots formed through the one or more sidewalls, wherein the slots are circumferentially spaced around the one or more sidewalls of the collet and are vertically or angularly extending from at least one of the first open end, the second open end, and a point between the first open end and the second open end, the collet having a longitudinal length, the one or more sidewalls having a cylindrical outer surface the entirety of which is parallel to a central axis of the collet and an inner surface including a plurality of grooves for providing debris relief; and - a hollow sleeve positioned in the region between the retaining device and the various indents, protrusions or shoulders, and covering the collet, the sleeve having a first end and a second end opposite the first end of the sleeve, wherein the sleeve is radially flexible and configured to be radially actuated to press against the one or more sidewalls of the collet with sufficient force to flex portions of the collet to grip the translatable component, the sleeve having a longitudinal length less than the longitudinal length of the region between the retaining device and the various indents, protrusions or shoulders; - a first seal contacting the sleeve near the first end of the sleeve; - a second seal contacting the sleeve near the second end of the sleeve; - a preload ring positioned near and spaced from the second open end of the collet, the preload ring further being positioned between the hollow sleeve and the translatable component; and - a preload O-ring positioned between the preload ring and the collet.