2" 90° Mirror Diagonal for Refractor with 1.25" adaptor.

The body of the all-metal Moonfish® 2" 90° Mirror Diagonal for Refractors is machined from a single piece of aluminium to guarantee a perfect 90° mirror angle. It has a strong screw tensioner, essential for firmly holding those expensive (and heavy) 2" eyepieces. It also comes with a convenient 1.25" adaptor.

All-metal and glass. The only plastic parts are the dust-caps!

The mirror surface is coated onto a thick base of 12mm float glass. The reflective aluminium coating is polished to a minimum of 1/6th lambda (more typically 1/8th lambda) and given a silicon protection coating for longevity in the field.

The 1.25" adaptor fits perfectly into the 2" diagonal. It has the standard screw tensioner to safely hold all 1.25" eyepieces and other 1.25" accessories. Unusually, the 1.25" adaptor is itself threaded for 2" filters.

This product is for refractors only, or other telescope designs with unthreaded focusers. It is not threaded for the rear cell of an SCT.