Odd copper tube cap. Odd in that it's lighter than the old ones, and is a not domed. But that wri...Odd copper tube cap. Odd in that it's lighter than the old ones, and is a not domed. But that written, this cap also has three protrusion on cap inside edge, see pics. For commercial/slamming pipe plumbing the lightness of cap would be a blessing, lees weight when packing bunches. The ID diameter of cap is slightly over 9/16" whcih will work just fine with the OD of K"0.527, L"0.545, M"0.569. For the DIY gent/lass what this means is it will work on your copper pipe.
by RUBEN