Firewall rule syntax on Debiana fork?

Question

linux

Good afternoon! It is necessary to understand some of the rules applied on the organization's firewall. Unfortunately, there is only a config in notepad, in the settings of itables I am a complete noob, I need to understand some of the nuances.

IPv4 Firewall "lan2wan":
Active on (eth0,IN)
rule action proto packets bytes
---- ------ ----- ------- -----
10 drop tcp 226813 11484584
condition - saddr !192.168.0.4 daddr 0.0.0.0/0 tcp dpt:25
10000 accept -- 135119132311 RETURN
condition - saddr 0.0.0.0/0 daddr /*

As I understand it, rule 10 rejects any TCP traffic on port 25, outgoing to any host from any host, except 12.168.0.4. Is it so?
And what does the 10000 rule do?
There are also the following rules:

IPv4 Firewall "wan2lan":
Active on (pppoe0,IN)
rule action proto packets bytes
---- ------ ----- ------- -----
10 accept -- 920554389819 RETURN
condition - saddr 0.0.0.0/0 daddr /* RELATED,ESTABLISHED
20 accept tcp 16 960
condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 match-SRC-ADDR-GROUP VT tcp dpt:33
89
24 accept tcp 0 0
condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 match-SRC-ADDR-GROUP VT tcp dpt:33
894

What fulfills the 10th and 20th rules? And does it make sense that the 20th rule repeats the 24th?