Installed this popup drain last weekend and was impressed with the solid chrome plated brass material it is made of. I however noticed a slight wobble of the inside tube as I tightened down the basin nut onto the sink drain. I snugged the nut as tight as I dared to on a porcelain sink and ran three tests upon completion. first was a full sink of warm water. Stopper held and when released allowed a full drain. No leaks observed. Next test running hot water. No leaks observed. Final test, running cold water. a small leak observed from the inner tube area. Just a drip or two but non the less a leak. I haven't investigated as to why it leaks but I do attribute it to that little wobble I noticed as I tightened up the basin nut from below. Hopefully its not a design fault. Cold water temperature was around 43°F ( 6°C).