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I'm sure it's made for them by a reputable manufacturer. Looks a lot like a dynotech, except for needing to replace the pinion flange, which dynotech doesn't need to do. I don't have personal experience with a 4" shaft but have heard that they can run into clearance issues with safety loops.
I know I sound like a shill for DSS but outside of that, if you have to swap axle flanges you nee to recheck pinion depth, preload and backlash. If not you risk noise or worse burning up a gear. If you are swapping gears or diff then no additional cost but if not add time or money to this swap.