diff --git a/plugin_test.go b/plugin_test.go
index 8527125..6921da9 100644
--- a/plugin_test.go
+++ b/plugin_test.go
@@ -19,9 +19,9 @@ func TestInvalidConfig(t *testing.T) {
 
 func TestTLSCipher(t *testing.T) {
 	cfg := CreateConfig()
-	cfg.Headers.Cipher = "X-TLS-Cipher"
+	cfg.Headers.Cipher = "X-Tls-Cipher"
 	next := http.HandlerFunc(func(_ http.ResponseWriter, r *http.Request) {
-		assertHeader(t, r.Header, "X-TLS-Cipher", "TLS_AES_128_GCM_SHA256")
+		assertHeader(t, r.Header, "X-Tls-Cipher", "TLS_AES_128_GCM_SHA256")
 	})
 	handler, err := New(context.Background(), next, cfg, "traefik-tls-headers-plugin")
 	if err != nil {
diff --git a/readme.md b/readme.md
index 26af879..10ce4e0 100644
--- a/readme.md
+++ b/readme.md
@@ -13,7 +13,7 @@ middlewares:
     plugin:
       tlsheaders:
         headers:
-          cipher: X-TLS-Cipher
+          cipher: X-Tls-Cipher
 ```
 
 ## Supported fields
@@ -64,7 +64,7 @@ spec:
   plugin:
     tlsheaders:
       headers:
-        cipher: X-TLS-Cipher
+        cipher: X-Tls-Cipher
 ```
 
 </details>
diff --git a/testconfig/dynamic.yml b/testconfig/dynamic.yml
index 1bf63a1..c9ecda4 100644
--- a/testconfig/dynamic.yml
+++ b/testconfig/dynamic.yml
@@ -19,4 +19,4 @@ http:
       plugin:
         tlsheaders:
           headers:
-            cipher: X-TLS-Cipher
+            cipher: X-Tls-Cipher