Canon EF 600mm f4.0 L IS USM Telephoto Lens has been discontinued, here are some related products you might like:
The world's first 600mm lens with an Image Stabilizer for added steadiness and sharpness when working at slower shutter speeds. It shares the same lightweight, weather-resistant construction as the 300, 400 and 500mm IS Super Telephoto lenses, as well as their improved control layout, improved weight distribution, and mechanical manual focus.
- Flourite & UD elements eliminate secondary spectrum chromatic aberration.
- AF speed is the fastest in the world.
- Full-time manual focus override.
- AF Stop function shuts off autofocus when an obstruction appears
- Dust & moisture resistance made exceptional by magnesium alloy lens barrel and new rear gasket at lens mount.
- Two-stage image stabilization; dual-axis camera shake correction or vertical axis only(for panning).
- 3-stage focus limiter.
- Focus preset function allows for returning to a specifically set focus by turning a ring in front of the focus ring.
More information about Canon Products and Lenses: (Link to Canon Website)