Rem 20gauge magazine extend where to find?

[Zack]

I am looking for a Rem 20g magazine extend for a 21 inch barrel, My gun only holds 4 so I am looking to upgrade to 6. Where can I find one that FITS the 20g? all I see is 12g and those will not fit. I have to file the dimples off, will this effect some law like 992(r) ??

 

[jdh]

http://www.tjgeneralstore.com/magazine_extensions.htm
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