I bought these filters for my hoover t series wind tunnel and the filters were recommended for the model I have there , but as several people have mentioned, the bottom filter, which is meant to slide forward, doesn't snap into place like the original filter. It pops out when you suck. I ended up putting two pieces of tape on each side to hold the filter in place and it worked! My vacuum cleaner has found a new life! The suction power is much better. If the filter works I would give it a rating of 5 so maybe something can be fixed for the future. Otherwise they work as they should and the price was reasonable!