UK Number is giving you a free UK phone number - wherever you are in the world!
Please note: Once you get your number you must confirm and activate it by making a test call to it within a week. To keep your number active it must be used at least once every three months otherwise it will be deactivated and made available to other users
You have to enter the SIP-address and your email into the given form. In my case I has been the destination address too long for the form. I needed to send an email to the support and it has been functioning within 24 hours.