It features Arca-compatible dovetail which allow you attach your lens to Ball Head, Clamp or Panorama Head of Arca-Swiss standard. Designed for Canon 400mm F2.8 IS/ISII/ISIII, 500mm F4.5 L, 500mm f/4 L IS/ISII, 600mm F4 IS/ISII/SIII, 800mm F5.6 IS Lens.
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