This is most likely a helmet manufactured by Beijing Rodia (http://www.chinahelmet.com.cn/
). These helmets are floating around under thousands of different names.
You can check if the FIA8858-2002 (HANS) certification is legit on the FIA website (FIA
> Drivers' Equipment).
You can check also if the SA2005/SA2010 certification is legit on the Snell Foundation website. Snell does buy certified helmets on the open market and tests them continuously, so if the manufacturer were to decide to save costs by building cheaper helmets after certification Snell would revoke the certificate.
I bought this helmet two years ago and asked the seller before who manufactured it. This allows you to check with the available documents if it is really certified.
Market prices here have been 270-330€ for the SA2005 version, but be aware that there is a SA2010 version now for the same price.