I had the speedfeed standard shell holder stock on my Mossberg 590 20" from the factory. It was a great stock but I swapped it for a speedfeed with shell holders and pistol grip. I will be adding the standard speedfeed shell holder stock to an 870 when I stop procrastinating.
The shell holders are not noticeable when shooting/shouldering the gun. Go to our site Sunflowerammo.com
, shoot me an email with details and I can get you a quote. We do not stock them but I can get them from my local distributor same day.