The sink in our new home did not come with a stopper, and after two generic stoppers purchased at hardware stores were too small for our InSinkErator drain, the search on Amazon began! Since the stoppers in this listing stated that they were by InSinkErator, I hoped that meant they would actually fit. I purchased the plain black, and the STP-DS Silver Saver Sink Stopper, Polished Stainless Steel, and both fit perfectly and seal tightly to fill the sink.I love the stainless dual-position stopper (STP-DS)! Our sink has a single drain with a disposal, and this stopper looks great and grips tightly in place, yet is easily removed when needed. I love that I can leave it in place all of the time, just pulling up the silver part of the stopper and slightly twisting to the open position. Water and smaller food can go down the drain to the disposal, but large items (like spoons!) are kept out. I can run my disposal with the stopper in the open position, and a quick twist allows the stopper to close to fill the sink for dishwashing. Brilliant! It was expensive (I know, it's just a sink stopper, right?), but I must say that for me it is worth it for the good looks and convenience of use, and since it stays in the drain, not having to find a place to put the stopper when not in use. I only wish that the silver top part of the stopper would stay perfectly straight when in the open position, as it tips slightly to the side (not enough to remove a star!).I wasn't sure how the stainless stopper was going to work out, so I had also ordered the plain black stopper (STP-PL Plastic Sink Stopper, Black). It's a basic stopper like I am used to having, made of hard plastic with a rubbery feeling seal that grips tight. I kept it as a back-up.