Get close up to your subjects with this 52mm slip-on macro lens for Sport HD. Close up focusing range underwater (with water in space between lens and pens port) approximately 6 inches to 3.5 feet/15cm to 1.0 meter. Close up focusing range on land (with air in space between lens and lens port) approximately 1.2 inches to 6 inches/3cm to 15cm. Magnification: +12. Lens material: K9 optical glass. Dimensions: (0.75 x 2.7) inches / (2.0 x 7.0)cm. Weight 2.5 oz / 70g.