diff --git a/prebuilt/common/bin/backuptool.sh b/prebuilt/common/bin/backuptool.sh
index 25c1d0d..9b8bbae 100755
--- a/prebuilt/common/bin/backuptool.sh
+++ b/prebuilt/common/bin/backuptool.sh
@@ -5,7 +5,7 @@
 
 export C=/tmp/backupdir
 export S=/system
-export V=10
+export V=Slim-4.3
 
 # Preserve /system/addon.d in /tmp/addon.d
 preserve_addon_d() {
@@ -20,6 +20,14 @@
   rm -rf /tmp/addon.d/
 }
 
+# Check for proper Slim version
+check_version() {
+  if ( ! grep -q "ro.slim.version=$V.*" /system/build.prop); then
+    echo "Not running backup from incompatible version"
+    exit
+  fi
+}
+
 # Execute /system/addon.d/*.sh scripts with $1 parameter
 run_stage() {
 for script in $(find /tmp/addon.d/ -name '*.sh' |sort -n); do
@@ -29,15 +37,15 @@
 
 case "$1" in
   backup)
+    check_version
     mkdir -p $C
-    check_prereq
     preserve_addon_d
     run_stage pre-backup
     run_stage backup
     run_stage post-backup
   ;;
   restore)
-    check_prereq
+    check_version
     run_stage pre-restore
     run_stage restore
     run_stage post-restore