As a footwear expert with extensive knowledge in sizing and fit, I can provide you with a detailed explanation of what "B" and "M" mean in shoe sizes.

In the United Kingdom and other countries that follow the British sizing system, "B" stands for "Medium" and "M" stands for "Medium" as well. However, the use of "B" and "M" can vary slightly in different regions. In the UK, "M" is often used to denote a medium width, while "B" is less commonly used and can sometimes indicate a slightly wider fit, but this is not a strict rule and can vary by manufacturer. It's important to note that the actual width of the shoe can differ from one brand to another, even if they both use the same letter to indicate width.

Here's the translation in Chinese:

作为一位对鞋码和合适度有广泛知识的鞋类专家，我可以为您提供关于鞋码中的"B"和"M"所代表含义的详细解释。

在英国以及遵循英国尺码系统的其他国家，"B"代表“中等（Medium）”，而"M"也代表“中等（Medium）”。然而，在不同地区使用"B"和"M"可能会有轻微的变化。在英国，"M"通常用来表示中等宽度，而"B"使用较少，有时可能表示略宽的合身度，但这不是严格规则，可能会因制造商而异。需要注意的是，即使两个品牌都使用相同的字母来表示宽度，实际的鞋子宽度也可能有所不同。

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9 is the length and B is the width. The (M) stands for "medium." B always represents medium, the (M) is redundant. I guess they say (M) in case someone doesn't know what width the B represents. AA is narrow, D is wide.read more >>