diff --git a/pw_kvs/public/pw_kvs/flash_memory.h b/pw_kvs/public/pw_kvs/flash_memory.h
index 8a3d35d0..b767386 100644
--- a/pw_kvs/public/pw_kvs/flash_memory.h
+++ b/pw_kvs/public/pw_kvs/flash_memory.h
@@ -232,7 +232,7 @@
   // UNKNOWN - HAL error
   // TODO: Result<bool>
   virtual Status IsRegionErased(Address source_flash_address,
-                                size_t len,
+                                size_t length,
                                 bool* is_erased);
 
   // Check if the entire partition is erased.