The conntrack-tools are a set of userspace tools that allow system 
administrators to interact with the Connection Tracking System (the 
module that provides stateful packet inspection for iptables). The 
conntrack-tools include the userspace daemon conntrackd and the 
command line interface conntrack. 

This requires libnfnetlink and libnetfilter_conntrack, both of which
are also available from SlackBuilds.org.