Nordic MXT 12ga Benelli Nova/Supernova, Beretta and CZ Extension Nut Fits Beretta 1301, Xtrema, Xtrema2, A400 (Xtreme & Xtreme Plus Only), Benelli Nova/Supernova, CZ 712/912

The BR-model nut is compatible with the following 12 gauge shotguns:

Benelli Nova and Supernova
Beretta 1301 Competition and Tactical
Beretta 391 Xtrema and Xtrema II
Beretta A400 Xtreme and Xtreme Plus
CZ 612, 712, and 912
Weatherby SA-08
Fabarm STF 12 - Will fit but a small gap will be left internally between the two magazine tubes.