diff --git a/Parameters.md b/Parameters.md
index 874b506..4c71210 100644
--- a/Parameters.md
+++ b/Parameters.md
@@ -9,7 +9,7 @@ function animation. Some simulations use variants of the published code. The lis
 updated gradually. 
 
 
-### 5 September 21 -  ###
+### 5 September 21 - A Sinai pinball with finite horizon ###
 
 **Program:** `particle_pinball.c`