Quarles & Brady
Toilet flange
 A toilet flange is disclosed for mounting a toilet to a floor and for connecting the toilet to a drain pipe leading to a sewer pipe. The toilet flange has an axial bore which is initially closed at the top by an integral knock out element which seals the bore for air or water testing prior to the installation of the toilet. The knock out element when removed is larger than the lumen of the drain pipe so that it cannot fall into it. 
E
E03D
inventional
James
Piskula