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

Results forcustspf5.register.com

Resolver

Location

TXT

Name	TTL	Value
custspf5.register.com	1800	v=spf1 ip4:69.156.243.45/24 ip4:216.21.229.220 ip4:209.16.96.0/20 ip4:96.9.0.0/18 ip4:207.204.0.0/18 ip4:63.240.103.9 ip4:63.240.89.35 ip4:63.240.89.31 ip4:63.240.103.58 ip4:63.240.103.59 ip4:63.240.103.60 ip4:206.65.164.0/24 ip4:206.65.163.0/24