It is basically the main registry of ccTLDs, known as country-code top-level domains which are implied on the only domains ending with .ch as well as .li. After the successful completion of the payment process, one can enjoy the module.
The best place to start if you need help with a specific product is to contact the developer. All WHMCS Marketplace developers have both a website and support URL listed.
Version 3.0.4 Stable Build
#New Feature :
DNSSEC Feature added with Switch EPP Login Command.
Make the certificate field optional.
The OpenSRS Domains Pro module allows you to register, renew and transfer domains from an ever-expanding selection of TLDs, including many new gTLDs. This module supports domain locking and WHOIS Privacy for select TLDs, as well as WHMCS Domain Sync.
Official GoDaddy Wholesale Domain Registrar Module
The ISPAPI Registrar Module connects WHMCS to your HEXONET account.
High-performance Domain Availability Checks using Hexonet's registrar API
ZA Domains CO.ZA WHMCS Module - Free Module for CO.ZA Domain Resellers and Domain Registrars