Thank you for your reply. I check links you referred to me. There is no where to say the operating temperature range. I also checked the spec of Samsung S5P4418 CPU which is used for those boards, the operating temperature is TBD. I really doubt about that those boards can meet -40C to +80C.

I was thinking to use Nanopi for a project, but I couldn't find any spec on temperature range. For industry application, -40C to +80C is required. Is there any product can meet that requirement?