Choat tool 8 round extension for remington 870 - Choate Tool Remington 870/1100/1187/Versamax 8 Shot Extension +3Rounds

Installed it yesterday, but did not try and load 7 rounds in the tube magazine. I tried that today. It told me NO...it only would take 4 rounds. So I pulled it back apart and realized I needed to drill out the "dimples" the instructions referred to, once I did that, no problem.
It loaded and unloaded all 7 round as designed. This is the 2nd one I have bought in the last few months. The other was for a Smith & Wesson 3000, it was equally easy to install and it functioned as intenderd