The CLASSIFY target

Hi!
I have the next rule in my script:
iptables -t mangle -A FORWARD -i $EXT -o $INT -m mark --mark 2 -j CLASSIFY --set-class 1:A
should i poit it to one of the htb subclasses or to the leaf qdisc? iptables -t mangle -A FORWARD -i $EXT -o $INT -m mark --mark 2 -j CLASSIFY --set-class A:
Can someone help me please?