diff --git a/pytec/tec_qt.py b/pytec/tec_qt.py
index 91299a4..44ccdb3 100644
--- a/pytec/tec_qt.py
+++ b/pytec/tec_qt.py
@@ -154,6 +154,8 @@ class ClientWatcher(QObject):
 
 
 class ChannelGraphs:
+    """Manager of the two graphs of a channel, and its elements."""
+
     """The maximum number of sample points to store."""
     DEFAULT_MAX_SAMPLES = 1000