diff --git a/src/main/java/de/ids_mannheim/korap/KrillQuery.java b/src/main/java/de/ids_mannheim/korap/KrillQuery.java
index b12829b..ec028f0 100644
--- a/src/main/java/de/ids_mannheim/korap/KrillQuery.java
+++ b/src/main/java/de/ids_mannheim/korap/KrillQuery.java
@@ -903,6 +903,12 @@
                     value.append(constraint.get("layer").asText());
                     value.append(':').append(unit);
                     unit = value.toString();
+                }
+
+                // Use default foundry and layer - currently only base is supported!
+                else if (unit.equals("s") || unit.equals("p")) {
+                    StringBuilder value = new StringBuilder();
+                    unit = value.append("base/s:").append(unit).toString();
                 };
 
                 // Sanitize boundary
diff --git a/src/test/java/de/ids_mannheim/korap/index/TestElementDistanceIndex.java b/src/test/java/de/ids_mannheim/korap/index/TestElementDistanceIndex.java
index d722038..1e8df6f 100644
--- a/src/test/java/de/ids_mannheim/korap/index/TestElementDistanceIndex.java
+++ b/src/test/java/de/ids_mannheim/korap/index/TestElementDistanceIndex.java
@@ -117,6 +117,7 @@
 
         SpanQuery sq;
         sq = createQuery("s", "s:b", "s:c", 0, 2, true);
+
         kr = ki.search(sq, (short) 10);
 
         assertEquals(kr.getTotalResults(), 4);
@@ -228,6 +229,9 @@
 
         SpanQuery sq;
         sq = sqwi.toQuery();
+
+        System.err.println(sq.toString());
+
         kr = ki.search(sq, (short) 10);
 
         assertEquals((long) 3, kr.getTotalResults());