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Use the Farpoint Astro 1.25" Eyepiece Parfocal Ring to make your mismatched eyepieces parfocal and eliminate the need to refocus when you want to change magnifications. This 4-pack of rings is perfect if your collection is made up of eyepieces from different series or manufacturers and you want to make your telescope time easier.
Eyepieces with different focal lengths and/or from different manufactures will often have different nosepiece lengths which require you to adjust the focus point when you change eyepieces, but parfocal eyepieces have the same length nosepiece which allows you to change eyepieces without refocusing. The parfocal ring fits over the nosepiece and is set in the desired position with a simple setscrew—this lets you set the depth that your eyepiece will sit into a drawtube holder or accessory, like a diagonal or Barlow, that will make it parfocal with others, while only adding 0.267" of optical length.