Set-Rite - Toilet Flange Extender Kit (1/4" to 3/8") Toilet Flange Repair Extender Kit - Extends from 1/4" to 3/8" to Finished Floor Code Approved - Provides a Water & Gas Tight Seal (IAPMO) Our Extender & Spacers measure 7-1/4" in diameter, just slightly larger than a 7" flange. Unique Design for Remodeling with Snap-in-Half Design to use under existing flanges Use on Cast Iron, Lead Bends, PVC & ABS Flanges or Uneven Surfaces