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

Results forspf.extole.io

Resolver

Location

TXT

Name	TTL	Value
spf.extole.io	300	v=spf1 ip4:168.245.95.253/32 ip4:192.254.121.111/32 ip4:168.245.95.253/32 ip4:149.72.150.41/32 ip4:192.254.120.212/32 ip4:50.31.62.65/32 ip4:192.254.121.106/32 ip4:192.254.121.110/32 ~all