All online payments are processed by FastSpring. Selecting a purchase button above will take
you to their secure website to process
payments, or visiting https://welsim.onfastspring.com to select items.
We will email you an official product key after receiving payment and your Computer ID
(Computer ID, in the format of xxxx-xxxx-xxxx-xxxx, is generated from WELSIM application
your computer). Here are the details about activation.