What are the different Canon tripod mount ring types for?

Question

What are the types of Canon's tripod mount rings? I've heard about A, B, C and D types, but have no idea what it means or what the difference between them is.

Answer

The different types are:

• Tripod Mount Ring A for 70-200mm f/4L (for both IS & non-IS versions)
• Tripod Mount Ring B for 100mm f/2.8 Macro, 180mm f/3.5L Macro & MP-E 65mm f/2.8 Macro
• Tripod Mount Ring D for 100mm F2.8 IS Macro Lens

They have (B) and (W) markings on them, meaning Black and White respectively. A and A-2 (II) are said to be interchangeable.

It seems that Canon does not make type C, but some third parties do.

According to different sources, B also fits for 100-400mm f4.5-5.6 and both IS and non-IS 70-200 f2.8.

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