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

Results forwww.admin.threshold.co

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2019-10-09T21:15:19.008	2019-10-09T20:15:18	2020-01-07T20:15:18	isitmangoseason.iclightmango.com	www.admin.threshold.co	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-10-09T21:15:18.363	2019-10-09T20:15:18	2020-01-07T20:15:18	isitmangoseason.iclightmango.com	www.admin.threshold.co	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-08-12T13:15:08.477	2019-08-12T12:15:07	2019-11-10T12:15:07	ndnganntcgiang.cf	www.admin.threshold.co	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-08-12T13:15:07.103	2019-08-12T12:15:07	2019-11-10T12:15:07	ndnganntcgiang.cf	www.admin.threshold.co	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-08-12T11:04:42.824	2019-08-12T10:04:42	2019-11-10T10:04:42	www.admin.threshold.co	www.admin.threshold.co	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-08-12T11:04:42.281	2019-08-12T10:04:42	2019-11-10T10:04:42	www.admin.threshold.co	www.admin.threshold.co	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3