Mag well addition legal USPSA Single Stack?

[Dudedog]

Looking at the rules and I can't determine for sure is something like this would be legal for single stack or not.

https://www.brownells.com/handgun-p...ousings/1911-ez-loader-magwell-prod16413.aspx
Small mag well does not extend past grip sideways

I see this in Prohibited mods
•External modifications or features such as
weights or devices to control or reduce recoil
(such as, but not limited to, thumb rests or
components which could be used as such).
So is that all external modifications not listed in authorized?

I don't see it spelled out as OK in authorized mods,
So is it legal because it is not listed in prohibited, or illegal (becomes limited gun) because it is not listed in Authorized.

Not trying to argue one way or the other.

Thanks in advance everybody.

 

[waktasz]

Legal as long as it fits in the box

 

[Dudedog]

Thanks, I appreciate it.

 

[8ring]

USPSA Handgun Competition Rules, February 2014 Edition
APPENDIX D5 —

Yes, handgun with empty magazine
inserted must fit wholly within a box
with internal dimensions of 8 15/16” x
6” x 1 5/8” (tolerance +1/16”, -
0”)
(8.938” x 6” x 1.625”) (227.01mm x
152.40mm x 41.28mm