diff --git a/docs/en_US/case/case4.md b/docs/en_US/case/case4.md
index c12079c8..44b6092d 100644
--- a/docs/en_US/case/case4.md
+++ b/docs/en_US/case/case4.md
@@ -3,7 +3,7 @@ Contributor:
 + [dysf888](https://github.com/dysf888)
 
 GitHub project: [fake-nezha-agent](https://github.com/dysf888/fake-nezha-agent)（Chinese）  
-
+Mirror backup, non-real-time update ：[fake-nezha-agent](https://github.com/nezhahq/fake-nezha-agent)（Chinese）  
 
 You can modify the monitoring data uploaded to Dashboard by the Agent  
 Use it for cheating 😈