While the Lone Peak Panniers are pretty darn water resistant the rain cover adds one more layer for greater protection.
Also the bright yellow does wonders for visibility.
Highly adjustable drawstring fit allows the cover to fit a wide range of pannier sizes.
Sold as a set of 2 rain covers.
Large -fits over Mt. Superior, Mt. Rainer, King's Peak
Small -Foothill, Sundance, Parleys Summit, and Millcreek panniers