This new 2"-1.25" low-profile eyepiece adapter allows you to just twist the silver locking ring and your 1.25 inch eyepiece, or collimator is centered precisely in your 2" focuser not pushed to one side like with thumbscrews. - Threaded for standard 2" (48mm) filters - Can be used with standard T-thread adaptors for cameras - Helical compression centering mechanism - Knurled twist-lock ring - Compression ring will not mar your eyepieces - Made from aluminum and plastic compression ring.