Canon EF 100mm f/2.8L IS USM Macro Lens for Canon Digital SLR Cameras 100 mm focal length and 1:2.8 maximum aperture. The EF1.4X II/EF2X II extenders cannot be used with this lens. There are no compatible close-up lenses. Lens construction consists of 15 elements in 12 groups. 23.4-Degree diagonal angle of view Inner focusing system with USM and full-time manual focus option.Closest focusing distance 0.99 ft./0.3m (maximum close-up magnification: 1x) 67 mm filter size 100mm lens with f2.8 aperture Canon's first mid-telephoto macro "L" series lens to include Canon's sophisticated Image Stabilization Near-silent Ultrasonic focusing Enjoy life-size close-up capabilities without an adapter Compatible with 67mm filters