Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Very Effective

These are a little bit touchy to install properly, but once in place, they are very effective. There is no doubt in my mind that when a toilet seat can move from side to side, it will, and over time that movement will loosen the seat's connection to the toilet. When it loosens, it will allow more movement, and so on, until finally it is so loose that it's unsafe, and you wind up replacing the whole seat. These little bumpers very effectively prevent the seat from sliding from side to side, and thereby prevent undue stress and strain on the connection to the toilet.There could be some better instructions and "templates" provided to place them properly, but otherwise, they are very good.