iptables-save file syntax

[cadilhac@xxxxxxx (Nicolas Cadilhac)]

Hi,

I wonder what are those numbers on these lines :

*nat
:PREROUTING ACCEPT [77070:3730176]
:POSTROUTING ACCEPT [2859:369253]
:OUTPUT ACCEPT [6476:595842]

sometimes it's 0:0 but since they are really big numbers they are not ports.
Also are these lines policies ?

Thanks