Hyperion 2\\\" Finetuning Stopring with brass clamping ring and 2 thumb screws.

Baaders Hyperion 2" Finetuning Stop Ring, with internal brass compression ring, is an additional accessory for Baader Hyperion eyepieces. It is used when combining a Hyperion Eyepiece and a 2" diagonal or prism and prevents the 1.25" eyepiece barrel from hitting and damaging the internal components, especially whenever additional Finetuning Rings (#2958214 or #2958228) are lengthening the original eyepiece body.