Karen Walker Black Super Duper Strength Black Sunglasses. Discontinued style. Super Duper Strength features an exaggerated round shape with a chunky frame that creates our striking silhouette. Crafted in a glossy black bio-acetate, the bold black frame is fitted with dark smoke mono lenses for a timeless, super chic look. - Provides good UV protection - Provides high protection against sun glare - Can be fitted with prescription lenses - Crafted in premium bio-acetate to phase out chemical additives and optimise biodegradability at end of life.