According to Strike Industries the overall width is 4 3/8in (111.13mm).
Yes, the Strike Industries Extended Latch AR Charging Handle will be compatible with an Aero Precision 9mm upper receiver.
The Strike Industries Extended Latch AR Charging Handle latch can be swapped out.
The Strike Industries Extended Latch AR Charging Handle is not compatible with the M&P15-22 as it uses a proprietary charging handle. I would recommend the TRYBE Defense Ambidextrous Charging Handle for Smith & Wesson M&P 15-22, found by using the link below:
https://www.opticsplanet.com/trybe-defense-ambidextrous-charging-handle-for-smith-wesson-m-p-15-2.html
Strike Industries does not provide specific dimensions of their Extended Latch AR Charging Handle. I'd recommend reaching out to them directly for more information.
No, the MR762A1 uses a proprietary charging handle that is not compatible with AR10/DPMS pattern .308 charging handles.
The Strike Industries Extended Latch AR Charging Handle will not work with the Sig MPX. The Sig MPX uses a modified charging handle, but the Radian Weapons Raptor LT SIG MPX Ambidextrous Charging Handle at the link below will work with the MPX Copperhead.
https://www.opticsplanet.com/radian-weapons-radian-raptor-lt-charging-hand-le-blk-sig-mpx-w-support-arm.html
Yes, The Strike Industries Extended Latch AR Charging Handle will fit and function as intended with your Radical Firearms SOCOM 5.56mm AR rifle.
The Strike Industries Extended Latch AR Charging Handle will work with Mil-Spec dimension AR15's in a variety of calibers. So it will work with a 450 Bushmaster AR.
The Strike Industries Extended Latch AR Charging Handle will replace Mil-Spec charging handles. Freedom Ordnance doesn't state if the FX-9 uses a Mil-Spec charging handle. I recommend contacting Freedom Ordnance to confirm compatibility of the Strike Industries Extended Latch AR Charging Handle with the FX-9.