diff --git a/about-mtu.md b/about-mtu.md
index d5e1f71..9f5810f 100644
--- a/about-mtu.md
+++ b/about-mtu.md
@@ -4,4 +4,8 @@ Since udp2raw itself doesn't have user space packet splitter, you have to tune t
 
 udp2raw support mtu at most 13xx depends on the upper level application (e.g. what kind of VPN you are using), I suggest to use `1200` as a safe value.
 
-However, if you are not happy with this or your upper level application doesn't allow you to tune MTU, there is indeed a way to by pass the MTU limitation, see [[https://github.com/wangyu-/udp2raw/wiki/bypass-mtu-limitation]]
\ No newline at end of file
+However, if you are not happy with this or your upper level application doesn't allow you to tune MTU, there is indeed a way to by pass the MTU limitation, see [[https://github.com/wangyu-/udp2raw/wiki/bypass-mtu-limitation]]
+
+
+#### if you simply want to disable the mtu warning
+By default udp2raw will warn you if it sees a packet larger than 1375, if you belive your link can send large MTU and you simply want to disable the warning, you can use `--mtu-warn 9999`.
\ No newline at end of file