diff --git a/java-11-openjdk.spec b/java-11-openjdk.spec
index 45e70e2..0cb9731 100644
--- a/java-11-openjdk.spec
+++ b/java-11-openjdk.spec
@@ -374,7 +374,7 @@ if [ "%{?1}" == %{debug_suffix} ]; then
   let PRIORITY=PRIORITY-1
 fi
 
-ext=.gz
+ext=%{_extension}
 alternatives \\
   --install %{_bindir}/java java %{jrebindir -- %{?1}}/java $PRIORITY  --family %{name}.%{_arch} \\
   --slave %{_jvmdir}/jre jre %{_jvmdir}/%{sdkdir -- %{?1}} \\