On submitting a request to transfer to 1st Domains you will be required to verify the request to ensure it is legitimate and that you are the rightful owner. Once the transfer request has been verified (by email to current WHOIS Registrant contact), 1st Domains will submit the transfer request to Verisign Global Registry.
Once a transfer request has been submitted to Verisign, the current registrar for the name will receive notification of the request. The Global Registry will allow the current registrar up to 5 business days in which to approve or decline the transfer request. You may or may not receive verification material from the current registrar.
Each registrar has their own policies concerning transfers away to another registrar. It is a good idea to contact your current registrar in order to make yourself familiar with their policies in order to avoid potential delays. Also some registrar's require you to have your domain with them in order to use their services, so please check with them to make sure that any services you have with them will continue to work once the domain has been transferred to 1st Domains. If those services are to stop working when the domain name is transferred away you will need to look at moving those services to 1st domains.
Some registrars have names locked against transfers that must be removed before a request can be submitted and some may send a verification email to verify the transfer away.
.com .net .org .biz and .info domain names require an Auth code or sometimes call a EPP code for transfer. You can request this from your current Registrar.
gTLD transfer process can take upto 5 - 10 days to complete
You can initiate the transfer using the transfer page here: https://1stdomains.nz/transfer/