For reasons not fully understood, ducks are not as attracted to spinning wing decoys on cloudy days, especially days of low cloud ceilings, and often are hesitant to land in close proximity. It seems that the i??flashi?? is more than desirable in these conditions. MOJO has experimented for a number of years with wings that offer more subdued finishes that are most effective on these days. No adjustments needed. Just replace the original magnetic wings with the Cloudy Day Wings.