diff --git a/src/main/java/com/svlada/security/auth/jwt/extractor/JwtHeaderTokenExtractor.java b/src/main/java/com/svlada/security/auth/jwt/extractor/JwtHeaderTokenExtractor.java
index 93fa2f9..2bfaa0d 100644
--- a/src/main/java/com/svlada/security/auth/jwt/extractor/JwtHeaderTokenExtractor.java
+++ b/src/main/java/com/svlada/security/auth/jwt/extractor/JwtHeaderTokenExtractor.java
@@ -14,7 +14,7 @@ import org.springframework.stereotype.Component;
  */
 @Component
 public class JwtHeaderTokenExtractor implements TokenExtractor {
-    public static String HEADER_PREFIX = "Bearer ";
+    public static final String HEADER_PREFIX = "Bearer ";
 
     @Override
     public String extract(String header) {