diff --git a/app/src/main/java/ru/ytkab0bp/slicebeam/utils/Prefs.java b/app/src/main/java/ru/ytkab0bp/slicebeam/utils/Prefs.java
index 4b754e4..26afc55 100644
--- a/app/src/main/java/ru/ytkab0bp/slicebeam/utils/Prefs.java
+++ b/app/src/main/java/ru/ytkab0bp/slicebeam/utils/Prefs.java
@@ -32,7 +32,7 @@ public class Prefs {
     }
 
     public static void setScaleInputInMM(boolean v) {
-        mPrefs.edit().putBoolean("scale_input_mm", true).apply();
+        mPrefs.edit().putBoolean("scale_input_mm", v).apply();
     }
 
     public static boolean isScaleLinked() {