Why Avast create automatic VPN-ESP rule?? I delete rule but at reboot came back.

[electricdream75]

Hello everyone, in the rules packet of public network profile of firewall I deleted all the rules and I specified what I needed, but avast, unless I did, created a rule for outgoing traffic: VPN-ESP protocol 50.
If I delete reappears every time i restart the computer. You know explain why avast created this rule unless I tell him?
It could be related to some service by default?

Thanks to all.