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

Results forcustspf3.register.com

Resolver

Location

TXT

Name	TTL	Value
custspf3.register.com	1800	v=spf1 ip4:69.49.123.245/32 ip4:216.251.43.181/32 ip4:216.251.43.180/32 ip4:69.156.240.70/32 ip4:216.251.43.157/32 ip4:216.251.43.182/32 ip4:69.49.111.68/24 ip4:69.49.111.75/24 ip4:69.49.111.76/24 ip4:69.156.243.37/24 ip4:69.156.243.44/24