ATI Outdoors Gen II Side Saddle, 9 Shell Customizable, Fits Mossberg 500/590, Fits with Modifications Remington 870, Winchester SXP and Maverick 88, Black Finish A.5.10.2551
GG&G, Inc. Side Saddle Shell Holder, Fits Mossberg 500, 590 12 Gauge, Angle Facilitates Bottom Loading of the Magazine Tube and Top Loading of the Chamber, Black Finish GGG-1515