50-200mm f/2.8 World's only 100-400mm equivalent super-telezoom with a constant f/2.8 aperture 5-axis sync IS: Handheld stability up to 7 stops image stabilization IP53-certified: Splash and dustproof design for any weather condition Up to 800mm F5.6: Extend up to 800mm F5.6 with the MC-20 teleconverter