I have a prefinished red oak floor. I fixed a couple of squeak spots with countersunk trim head screws. I filled the holes with a color matched putty. The floor sheen is semi gloss. I have a can of high gloss poly. My understanding is that flattening agents are added to take the original high gloss to semi gloss and more flattening agent added to get to matte gloss. Anybody know what the flattening agent is? I would like to flatten the high gloss stuff I have instead of having to buy a full can of semi gloss.