Tighten Connections and Test for Leaks

What happens here

Secure the new tailpiece by hand-tightening the new metal coupling nut onto the sink basket threads. Then, connect the P-trap to the new tailpiece and hand-tighten its slip nut. The plumber emphasizes that these connections typically only need to be hand-tightened, not overtightened with tools, as excessive force can strip threads or damage plastic components. Once all connections are secure, turn on the water at the sink and allow it to drain to check for any signs of leakage around the newly installed parts.

Goal: Hand-tighten all connections for the tailpiece and P-trap, then run water to check for any leaks.