Toilet Seal, Part # 7530P24, Wax-Free, "Better than Wax", Provides a solid seal for flanges above, at or below floor level, With Bolts and Spacer FAQ:
Q: My toilet rocks and is raised off the floor by 3/16" or less. What should I do? A: Use toilet shims.
Q: My toilet rocks and is raised off the floor by 1/4" or more. What should I do? A: Use a toilet base plate.
Q: Do i need to use the Spacer? A: No. The spacer is to be used when the floor flange is below the surface of the floor.
Can I stack (2) of the blue (non-wax) gaskets together? A: Yes, the non-wax gaskets are stackable.