Don't buy a helmet without a "live" fit. If you still decide to order a helmet from an online shop, you should determine its size as follows:

Wrap the soft measuring tape around the head approximately 1/2 inch above the eyebrows, over the ears and at the widest point around the back of the head. It is best to ask for help with the measurement.

Compare your head size to the specific motorcycle helmet size. Each manufacturer offers different helmet sizes, so you will need to compare your head size to the sizing of multiple brands.

And one more thing - you should not buy a helmet without ears. After all, no one knows what “adventures” they got on in the past. You can save a small amount and then pay with your health. However, if you're dying to buy a used helmet, first make sure it hasn't been in an accident; secondly, that less than 5 years have passed since the previous owner bought it. After all, a helmet also has a lifespan. Even if it has not suffered any external damage, the internal filling has deteriorated over the years. It is made of soft and elastic materials that sag, “squeeze” and thin out over the years. Accordingly, the old helmet will not be able to absorb the impact.

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