Big dog posted the part for you. Look at the right side of the picture he posted. See how it looks like a T? That fits in to the notches in the forend tube nut.
The 870 can be broken down and cleaned with no tools other then something to push out the two trigger pins. On K-9 once my back up drop the shotgun in some really clasic Florida Muck. Then the nuckle head cycled it open which allowed that mess to get into the action. I used my belt buckle to get the pins started and then pulled them out. I broke the weapon down and washed it off in a ditch. I had no doubts it would function if needed after that washing. We did not need it, never found the pert but had a wonderful day and evening in the wilds of North Florida. Weapon was stipped and cleaned properly in the Armory the next day and was no worse for wear from it's adventure and Tram road ditch bath.
The 870 can be broken down and cleaned with no tools other then something to push out the two trigger pins. On K-9 once my back up drop the shotgun in some really clasic Florida Muck. Then the nuckle head cycled it open which allowed that mess to get into the action. I used my belt buckle to get the pins started and then pulled them out. I broke the weapon down and washed it off in a ditch. I had no doubts it would function if needed after that washing. We did not need it, never found the pert but had a wonderful day and evening in the wilds of North Florida. Weapon was stipped and cleaned properly in the Armory the next day and was no worse for wear from it's adventure and Tram road ditch bath.
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