diff --git a/libuavcan/include/uavcan/timer.hpp b/libuavcan/include/uavcan/timer.hpp
index 743cbd0870..61ed5ec9c4 100644
--- a/libuavcan/include/uavcan/timer.hpp
+++ b/libuavcan/include/uavcan/timer.hpp
@@ -64,7 +64,7 @@ class TimerEventForwarder : public Timer
     Callback callback_;
 
 public:
-    TimerEventForwarder(Scheduler& node)
+    explicit TimerEventForwarder(Scheduler& node)
     : Timer(node)
     , callback_()
     { }