diff --git a/tools/memory-model/README b/tools/memory-model/README
index 91414a49fac53c2bd37093204e6b03554c1ad9de..ea950c566ffd6281754d225493b7dd790078148d 100644
--- a/tools/memory-model/README
+++ b/tools/memory-model/README
@@ -20,7 +20,8 @@ that litmus test to be exercised within the Linux kernel.
 REQUIREMENTS
 ============
 
-The "herd7" and "klitmus7" tools must be downloaded separately:
+Version 7.48 of the "herd7" and "klitmus7" tools must be downloaded
+separately:
 
   https://github.com/herd/herdtools7