Sink drain has a flange that is sealed to the sink hole with a bead of plumber's putty. This flange is screwed into the drain body, which is tightened to the underside of the sink bowl with a locknut. The tailpiece, which may contain a pop-up stopper, attaches to a drain trap with slip-joint couplings.
Sink trap remains filled with water so sewer gasses won't enter; it's connected to a threaded nipple inserted in a T in the drain line. An escutcheon trim hides the connection.
Mechanical pop-up stopper is operated by a system of levers and rods. If this isn't working properly, the solution is usually just a matter of adjusting the clevis screw or the position of the pivot rod.
Flexible supply tubes carry water from shutoff valves at wall to threaded tailpieces on the faucet base.
