diff --git a/archaius-core/src/main/java/com/netflix/config/ConcurrentCompositeConfiguration.java b/archaius-core/src/main/java/com/netflix/config/ConcurrentCompositeConfiguration.java
index 237ee8ec..7b792202 100644
--- a/archaius-core/src/main/java/com/netflix/config/ConcurrentCompositeConfiguration.java
+++ b/archaius-core/src/main/java/com/netflix/config/ConcurrentCompositeConfiguration.java
@@ -121,7 +121,7 @@ public Set<String> getUsedProperties() {
 
     public Set<String> getAndClearUsedProperties() {
         Set<String> ret = usedPropertiesRef.getAndSet(ConcurrentHashMap.newKeySet());
-        return Collections.unmodifiableSet(new HashSet<>(ret));
+        return Collections.unmodifiableSet(ret);
     }
 
     private List<AbstractConfiguration> configList = new CopyOnWriteArrayList<AbstractConfiguration>();