This is the standard stainless steel counterweight included with HyperStar lenses for fork-mounted telescopes. It has a 1.25" barrel that fits into the visual back of the telescope to balance the weight of the HyperStar lens and camera on the front of the telescope. It is not needed with telescopes on German-equatorial mounts.
The weight has a threaded hole on the back to allow stacking of optional extra weights for heavier cameras.
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