Remington 870 with Hogue Stock, Magpul Forend and ATI Fluted Extension from rowdyroutson from Remington 870 Forum:

I had a gunsmith cut a vent rib down and I love it. Ran $40. Its a little longer than 18 inches because the ribs line up past 18 inches. ATI fluted plus 2 magazine extension With breacher cap lines up perfectly with it. The gun came with the factory 18.5 inch bad sight but didn’t like it. The vent rib makes it look better imo.

Remington 870 with Hogue Stock, Magpul Forend and ATI Fluted Extension

Remington 870 with Hogue Stock, Magpul Forend and ATI Fluted Extension