diff --git a/overlay.d/README.md b/overlay.d/README.md
index 1fba2532d6..23b64bdd13 100644
--- a/overlay.d/README.md
+++ b/overlay.d/README.md
@@ -67,7 +67,7 @@ such as `azure`, `aws`, `gcp`. The chrony config for these NTP servers
 should override other chrony configuration (e.g. DHCP-provided)
 configuration.
 
-25-azure-udev-rules
+25azure-udev-rules
 -------------------
 
 Add udev rules for SRIOV networking on Azure. The udev rules are also