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

Results for_sv3.bitrix24.com

Resolver

Location

TXT

Name	TTL	Value
_sv3.bitrix24.com	300	v=spf1 ip4:54.83.193.228 ip4:46.235.53.71 ip4:107.20.247.151 ip4:195.208.185.5 ip4:35.156.4.219 ip4:18.197.175.177 ip4:18.196.128.52 ip4:195.208.185.95 ip4:195.208.185.93 ip4:35.158.163.184 ip4:50.19.124.94 ip4:50.16.186.133 ~all