Askar 3" f/3.9 Full Frame Reducer for FRA600 - FRA600-RED

The Askar f/3.9 full frame 3" reducer features a 4 element optical design specifically for the FRA600 Quad Astrograph.  It offers 0.7X focal ratio reduction in focal ratio to shorten exposure times and effectively widen the field of view. Back focus is 55 mm.  The FRA600 Reducer has built-in M48X0.75 filter threads.