88-89% density ( 11-12% VLT) This mid contrast amber-brown filter is considered a marginal glacier density lens. It offers good flexibility from bright and clear to hazier conditions. This lens is also available as the Sierra Polar which will reduce glare further, but is not recommended where ropes or jumping crevasses are employed. Polarized lenses may also black out some LCD screens. Available in plastic and NXT, single vision and progressive.