UnderStrukk is a commercial font.
For a single-user license, which will allow you to use the font for non-personal use (anything commercial or anything distributed for free), please send at least US$5 or equivalent in your local currently via PayPal to firstname.lastname@example.org.
For multiple users, send at least US$4.50 for each user.
For non-profit use, such as a charity, please send US$2.
For any queries or requests, just email email@example.com with what you want to ask, and I'll get back to you as soon as possible. If you can, please include the name of the font in the email title so I can prioritise a reply to it. Cheers.
Thank-you for buying and downloading this font, and supporting me, allowing me to continue making fonts as long as I can!