Ive been using it for a few years. The spray oil (greenish) is the "new" formula. The red stuff in the bottle is the old formula. There was some speculation that the old stuff was eating away at the glue in the filters, due to the alcohol content. The new stuff doesn't have that issue.
I wash mine in the kitchen sink, then if the wife is away, put the filters in the dryer on low for quick drying
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