diff --git a/nodes/masks/flex_mask_base.py b/nodes/masks/flex_mask_base.py
index 9d4295b..ba917a8 100644
--- a/nodes/masks/flex_mask_base.py
+++ b/nodes/masks/flex_mask_base.py
@@ -24,8 +24,8 @@ class FlexMaskBase(FlexBase, MaskBase):
         
         # Add feature-specific inputs
         required.update({
-            "feature": ("FEATURE",),
-            "feature_pipe": ("FEATURE_PIPE",),
+            "feature_param": (cls.get_modifiable_params(),),
+            "feature_mode": (["relative", "absolute"], {"default": "relative"}),
         })
         
         # Merge optional inputs
@@ -48,6 +48,12 @@ class FlexMaskBase(FlexBase, MaskBase):
         FlexBase.__init__(self)
         MaskBase.__init__(self)
 
+    @classmethod
+    @abstractmethod
+    def get_modifiable_params(cls):
+        """Return a list of parameter names that can be modulated."""
+        return ["None"]
+
     @abstractmethod
     def process_mask(self, mask: np.ndarray, feature_value: float, strength: float, **kwargs) -> np.ndarray:
         """Process a single mask with feature modulation.
diff --git a/nodes/masks/flex_masks.py b/nodes/masks/flex_masks.py
index e643336..9f6676b 100644
--- a/nodes/masks/flex_masks.py
+++ b/nodes/masks/flex_masks.py
@@ -295,10 +295,10 @@ class FlexMaskBinary(FlexMaskBase):
 
     def main_function(self, masks, feature, feature_pipe, strength, feature_threshold, mask_strength, invert, subtract_original, grow_with_blur, **kwargs):
         # Call the parent class's apply_mask_operation with all parameters
-        return self.apply_mask_operation(
+        return (self.apply_mask_operation(
             masks, feature, feature_pipe, strength, feature_threshold, mask_strength,
             invert, subtract_original, grow_with_blur, **kwargs
-        )
+        ),)
 
 class FlexMaskWavePropagation(FlexMaskBase):
     @classmethod
@@ -399,10 +399,10 @@ class FlexMaskWavePropagation(FlexMaskBase):
 
     def main_function(self, masks, feature, feature_pipe, strength, feature_threshold, mask_strength, invert, subtract_original, grow_with_blur, **kwargs):
         # Call the parent class's apply_mask_operation with all parameters
-        return self.apply_mask_operation(
+        return (self.apply_mask_operation(
             masks, feature, feature_pipe, strength, feature_threshold, mask_strength,
             invert, subtract_original, grow_with_blur, **kwargs
-        )
+        ),)
 
 class FlexMaskEmanatingRings(FlexMaskBase):
     @classmethod