*PLUMBERSSTOCK EXPERT* responded:
Good day! We appreciate your interest in our Delta RP62472 Part Plastic Pop-up Assembly. The holes in the pop up assemblies are for sinks with an over flow drain. Sink basins will oftentimes, depending on the application, come with a hole in the bowl in case the bowl over flows. This hole allows excess water to go through the over flow hole and down the drain instead of spilling over the bowl onto the floor. If you wish to purchase this for your sink, click Add To Cart now to confirm your order! Thank you for shopping with plumbersstock.com - the perfect place to find high-quality products at low, low prices!