It can be anything! An apex, subdomain, or even a URL.

Results forwebmail.necttos.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2021-05-31T02:57:54.757	2021-05-31T01:57:54	2021-08-29T01:57:54	*.necttos.com	*.necttos.com	C=US, O=Let's Encrypt, CN=R3
2021-05-31T02:57:54.64	2021-05-31T01:57:54	2021-08-29T01:57:54	*.necttos.com	*.necttos.com	C=US, O=Let's Encrypt, CN=R3
2021-05-15T19:47:51.94	2021-05-15T00:00:00	2021-08-13T23:59:59	necttos.com	webmail.necttos.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-05-15T19:47:51.555	2021-05-15T00:00:00	2021-08-13T23:59:59	necttos.com	webmail.necttos.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-02-28T07:07:41.197	2021-02-28T00:00:00	2021-05-29T23:59:59	necttos.com	webmail.necttos.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-02-28T07:07:40.899	2021-02-28T00:00:00	2021-05-29T23:59:59	necttos.com	webmail.necttos.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"