diff --git a/km3io/offline.py b/km3io/offline.py
index 1ff221881f2d1077eaa1eea69e4626925c8f19f2..a811ae402ace0b5eb7902a64fcb40e856161108c 100644
--- a/km3io/offline.py
+++ b/km3io/offline.py
@@ -41,7 +41,7 @@ class OfflineReader(EventReader):
             "dir_y": "hits.dir.y",
             "dir_z": "hits.dir.z",
             "tot": "hits.tot",
-            "a": "mc_hits.a",  # hit amplitude (in p.e.)
+            "a": "hits.a",  # hit amplitude (in p.e.)
             "trig": "hits.trig",  # non-zero if the hit is a triggered hit
         },
         "mc_hits": {
diff --git a/tests/test_offline.py b/tests/test_offline.py
index 8adda39facd746a143ce7f0f69f38bb1c4b00b94..b4310b4ce73b782b324bc819f1a2d0b409eb5c04 100644
--- a/tests/test_offline.py
+++ b/tests/test_offline.py
@@ -406,6 +406,7 @@ class TestOfflineHits(unittest.TestCase):
         assert "channel_id" in self.hits.fields
         assert "t" in self.hits.fields
         assert "tot" in self.hits.fields
+        assert "a" in self.hits.fields
         assert "trig" in self.hits.fields
         assert "id" in self.hits.fields