diff --git a/ot_vector.h b/ot_vector.h
index c99a8b4..6b7fdf4 100644
--- a/ot_vector.h
+++ b/ot_vector.h
@@ -6,10 +6,12 @@
 
 #include "trackerlogic.h"
 
+/* These defines control vectors behaviour */
 #define OT_VECTOR_MIN_MEMBERS   4
 #define OT_VECTOR_GROW_RATIO    8
 #define OT_VECTOR_SHRINK_THRESH 6
 #define OT_VECTOR_SHRINK_RATIO  4
+
 typedef struct {
   void   *data;
   size_t  size;