J
jokerone
Guest
Expires 3 months after you get it, and below is NI's response when trying to use it to buy a product. 
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Hello Walter,
Thank you for your email. As per our online store policy, vouchers cannot be
applied to items that are already within a promotion. Vouchers can only be applied
to full priced new purchases.
We apologize for any inconvenience this may have caused. The promotion for The
Mouth ended on June 20th. You'll be able to apply your voucher at this time.
If you have any further questions, please feel free to let us know. We thank you
for choosing Native Instruments.
Kind regards
Peter
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Hello Walter,
Thank you for your email. As per our online store policy, vouchers cannot be
applied to items that are already within a promotion. Vouchers can only be applied
to full priced new purchases.
We apologize for any inconvenience this may have caused. The promotion for The
Mouth ended on June 20th. You'll be able to apply your voucher at this time.
If you have any further questions, please feel free to let us know. We thank you
for choosing Native Instruments.
Kind regards
Peter