diff --git a/build.gradle.kts b/build.gradle.kts
index 17d7236..b9106ad 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -8,7 +8,7 @@ plugins {
 }
 
 group = "dev.booky"
-version = "1.0.2-SNAPSHOT"
+version = "1.0.3-SNAPSHOT"
 
 val plugin: Configuration by configurations.creating {
     isTransitive = false
diff --git a/src/main/java/dev/booky/cloudprotections/listener/ProtectionListener.java b/src/main/java/dev/booky/cloudprotections/listener/ProtectionListener.java
index 00039b1..7d74192 100644
--- a/src/main/java/dev/booky/cloudprotections/listener/ProtectionListener.java
+++ b/src/main/java/dev/booky/cloudprotections/listener/ProtectionListener.java
@@ -197,9 +197,9 @@ public void onRedstone(BlockRedstoneEvent event) {
         }
     }
 
-    private boolean onPiston(Block piston, Iterable<Block> moved) {
+    private boolean checkPiston(Block piston, Iterable<Block> moved) {
         if (this.manager.isProtected(piston, ProtectionFlag.REDSTONE, null)) {
-            return true;
+            return false;
         }
 
         for (Block block : moved) {
@@ -207,17 +207,24 @@ private boolean onPiston(Block piston, Iterable<Block> moved) {
                 return false;
             }
         }
-        return true;
+
+        return true; // allowed
     }
 
     @EventHandler(ignoreCancelled = true)
     public void onPistonExtend(BlockPistonExtendEvent event) {
-        this.onPiston(event.getBlock(), event.getBlocks());
+        boolean allowed = this.checkPiston(event.getBlock(), event.getBlocks());
+        if (!allowed) {
+            event.setCancelled(true);
+        }
     }
 
     @EventHandler(ignoreCancelled = true)
     public void onPistonRetract(BlockPistonRetractEvent event) {
-        this.onPiston(event.getBlock(), event.getBlocks());
+        boolean allowed = this.checkPiston(event.getBlock(), event.getBlocks());
+        if (!allowed) {
+            event.setCancelled(true);
+        }
     }
 
     @EventHandler(ignoreCancelled = true)