Spears P110 Series PVC DWV Pipe Fitting, Flush Plug, 6 NPT Male

My landscapers mowed over my other cap (twice) that had a raised wrench nut on it for installation/removal. I replaced the last one with this flush one and they can mow right over it w/o issue (the top of the drain pipe is flush w/ the ground). The size says 6, but I measured it at around 6.5, but it must be a standard size as it fit w/o issue. The only issue is installation - because it has a recessed wrench connection port instead of the raised nut, you need to find something that will fit it to install it tight. If you have a regular plug with the raised nut, you can just flip it over and use it to tighten this flush one.

Hard to find and it fits perfectly to 6 drain clean out.

Got this because I mowed the head off my previous outside sewer line cleanout plug. Being completely stupid about this stuff I sweated this because A) Home Depot did not have anything over 4 and B) the previous plug measured 6.5 diameter. Once I thought about it I figured the plug had to be larger because of the need to mount a fitting to the end of the 6 pipe into which the plug goes. And since Im Prime member and Amazon had the flush head on this wtf was I worried about? Of course this fit fine and Im back in business. Got this in two days which was plenty of time (duct tape carried me over.) Hoping for many years of damage-free mowing with this one.

Does exactly what its supposed to do.

Perfect fit for the septic pipe. Now my lawn boy can mow over the cap.