The Plumber's Choice 3-1/2 in. Strainer Basket with Ball Post Replacement for Kitchen Sink Drains Stainless Steel and Rubber Stopper 017532IN - The Home Depot
3.5 Inch Square Stainless Steel Kitchen Sink Strainer with Removable B – FaucetGennie.com
Stainless steel Sink Drain Strainer plug square basket US type - Amazon.com
TSV Square Drain Cover for Shower, 5.5-inch TPR Drain Hair Catcher Flat Silicone Plug, for Bathroom and Kitchen White Filter Shower Drain Protection Strainer Stopper with Suction Cups - Walmart.com