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

Results forww38.smtp2.amplesample.net

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2025-09-17T20:45:53.938	2025-09-17T19:47:23	2025-12-16T19:47:22	ww38.smtp2.amplesample.net	ww38.smtp2.amplesample.net	C=US, O=Let's Encrypt, CN=R13
2025-09-17T20:45:53.718	2025-09-17T19:47:23	2025-12-16T19:47:22	ww38.smtp2.amplesample.net	ww38.smtp2.amplesample.net	C=US, O=Let's Encrypt, CN=R13
2025-06-16T07:23:52.306	2025-06-16T06:25:21	2025-09-14T06:25:20	ww38.smtp2.amplesample.net	ww38.smtp2.amplesample.net	C=US, O=Let's Encrypt, CN=R11
2025-06-16T07:23:52.066	2025-06-16T06:25:21	2025-09-14T06:25:20	ww38.smtp2.amplesample.net	ww38.smtp2.amplesample.net	C=US, O=Let's Encrypt, CN=R11