This optional accessory is designed to work strictly with the EF 50mm f/2.5 Compact Macro lens. Unlike typical life-size adapters, the Life Size Converter EF actually has optics that are optimized for high magnification when combined with the 50mm macro lens. Magnifications from 0.26x (approx. 1/4 life-size) to 1.0x (true life size) are possible, at increased working distances.
Lens Construction 4 elements in 3 groups Closest Focusing Distance 0.24m / 0.8 ft. (from film plane to subject) Max. Diameter x Length, Weight 2.7" x 1.4", 5.6 oz. / 67.6 x 34.9mm, 160g