diff --git a/README.md b/README.md
index b497492..4e34420 100644
--- a/README.md
+++ b/README.md
@@ -37,6 +37,23 @@ as you like.
 ## Modules
 
 
+### backlight
+
+
+Screen backlight info
+
+Available formatters:
+* brightness
+* max_brightness
+* percentage
+
+
+* `format` — format string (default: `{brightness}/{max_brightness}`)
+* `backlight` — backlight, see `/sys/class/backlight/` (default: `acpi_video0`)
+* `color` —  (default: `#FFFFFF`)
+
+
+
 ### battery
 
 
@@ -59,24 +76,7 @@ This class shows a clock
 
 
 
-### file.Backlight
-
-
-Screen backlight info
-
-Available formatters:
-* brightness
-* max_brightness
-* percentage
-
-
-* `format` — format string (default: `{brightness}/{max_brightness}`)
-* `backlight` — backlight, see `/sys/class/backlight/` (default: `acpi_video0`)
-* `color` —  (default: `#FFFFFF`)
-
-
-
-### file.File
+### file
 
 
 Rip information from text files
@@ -91,8 +91,8 @@ the value of that component.
 float or int.
 * `file` names a file, relative to `base_path`.
 
-transform is a optional dict of callables taking a single argument, a dictionary containing the values
-of all components. The return value is bound to `name`
+transforms is a optional dict of callables taking a single argument (a dictionary containing the values
+of all components). The return value is bound to the key.
 
 
 * `format` — format string
diff --git a/i3pystatus/__init__.py b/i3pystatus/__init__.py
index 92f783f..0345129 100644
--- a/i3pystatus/__init__.py
+++ b/i3pystatus/__init__.py
@@ -168,12 +168,19 @@ class ClassFinder:
         self.baseclass = baseclass
         self.exclude = exclude
 
-    def predicate(self, obj):
-        return inspect.isclass(obj) and issubclass(obj, self.baseclass) and obj not in self.exclude
+    def predicate_factory(self, module):
+        def predicate(obj):
+            return (
+                inspect.isclass(obj) and
+                issubclass(obj, self.baseclass) and
+                obj not in self.exclude and
+                obj.__module__ == module.__name__
+            )
+        return predicate
 
     def search_module(self, module):
         # Neat trick: [(x,y),(u,v)] becomes [(x,u),(y,v)]
-        return list(zip(*inspect.getmembers(module, self.predicate)))[1]
+        return list(zip(*inspect.getmembers(module, self.predicate_factory(module))))[1]
 
     def get_class(self, module):
         classes = self.search_module(module)
diff --git a/i3pystatus/backlight.py b/i3pystatus/backlight.py
new file mode 100644
index 0000000..1c2b5a3
--- /dev/null
+++ b/i3pystatus/backlight.py
@@ -0,0 +1,38 @@
+from i3pystatus.file import File
+
+__imported__ = [File]
+
+class Backlight(File):
+    """
+    Screen backlight info
+
+    Available formatters:
+    * brightness
+    * max_brightness
+    * percentage
+    """
+
+    settings = (
+        ("format", "format string"),
+        ("backlight", "backlight, see `/sys/class/backlight/`"),
+        "color",
+    )
+    required = ()
+
+    backlight="acpi_video0"
+    format="{brightness}/{max_brightness}"
+
+    interval=1
+    base_path = "/sys/class/backlight/{backlight}/"
+    components={
+        "brightness": (int, "brightness"),
+        "max_brightness": (int, "max_brightness"),
+    }
+    transforms={
+        "percentage": lambda cdict: (cdict["brightness"] / cdict["max_brightness"]) * 100,
+    }
+
+    def init(self):
+        self.base_path = self.base_path.format(backlight=self.backlight)
+
+        super().init()
diff --git a/i3pystatus/file.py b/i3pystatus/file.py
index f998c0d..193f339 100644
--- a/i3pystatus/file.py
+++ b/i3pystatus/file.py
@@ -16,8 +16,8 @@ class File(IntervalModule):
     float or int.
     * `file` names a file, relative to `base_path`.
 
-    transform is a optional dict of callables taking a single argument, a dictionary containing the values
-    of all components. The return value is bound to `name`
+    transforms is a optional dict of callables taking a single argument (a dictionary containing the values
+    of all components). The return value is bound to the key.
     """
 
     settings = (
@@ -46,38 +46,3 @@ class File(IntervalModule):
             "full_text": self.format.format(**cdict),
             "color": self.color
         }
-
-class Backlight(File):
-    """
-    Screen backlight info
-
-    Available formatters:
-    * brightness
-    * max_brightness
-    * percentage
-    """
-
-    settings = (
-        ("format", "format string"),
-        ("backlight", "backlight, see `/sys/class/backlight/`"),
-        "color",
-    )
-    required = ()
-
-    backlight="acpi_video0"
-    format="{brightness}/{max_brightness}"
-
-    interval=1
-    base_path = "/sys/class/backlight/{backlight}/"
-    components={
-        "brightness": (int, "brightness"),
-        "max_brightness": (int, "max_brightness"),
-    }
-    transforms={
-        "percentage": lambda cdict: (cdict["brightness"] / cdict["max_brightness"]) * 100,
-    }
-
-    def init(self):
-        self.base_path = self.base_path.format(backlight=self.backlight)
-
-        super().init()