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What is the purpose of a trap under the sink?
The trap does double duty, keeping sewer gases from coming up through the pipes and out of the sink, and preventing heavy debris from getting into your pipes.
What does a drain trap look like?
A drain trap is usually a U-bend, J-bend, or S-shaped, to create a seal with the water that settles in it. P-traps are another common variation. Some drain traps will have a cleanout on the bottom, which can be loosened and taken off to drain and clean out the trap without having to remove it entirely.
Are sink traps universal?
Sink drain traps come in the same universal sizes used for kitchen and bathroom sink drainpipes, 1-1/2 and 1-1/4 inches respectively.