United Domains

United Domains

http://www.uniteddomains.com/new-top-level-domain/build-domain-registration/
RU Center

RU Center

https://www.nic.ru/en/cgi/na.cgi?step=n_a.ntld&zone=build
Vautron AG

Vautron AG

https://www.vautron.de/domain/neue-domain-endungen.php
Marcaria

Marcaria

http://www.marcaria.com/register/domain/domain_registration_bulk.asp?country=GTLD-build
Netim

Netim

https://www.netim.com/en/domain-name/build-domain
Instra

Instra

http://www.instra.com/en/domain-names/newgtld/build-domain-registration/build
Safenames

Safenames

http://www.safenames.net/nTLD/NewGtldsByCategory.aspx