To transfer any domain name to another registrar you will need the Auth Code(Authorisation code). The Auth Code is sent to the current registrant's contact email for the domain name. Auto Codes expire within 30 days, so if you have exceed that amount you will have to request a new Auth code. You can request the Auth code from within your 1st domains account. 

To request a new Auth Code for your domain name, please follow the steps below:

1. Login to your 1st Domains account at https://www.1stdomains.co.nz/client/login.php.
2. Once logged in, click 'Manage Domains & Services'.
3. Click on the domain name you would like to request the Auth code for.
4. Next, click the 'Request Key' link under Authorisation Key (UDAI/EPP), and the Auth Code will be emailed to the registrant contact.

You will then need to provide the new auth key to your new registrar and follow their instructions for the transfer to take place.