diff --git a/pyaccuwage/model.py b/pyaccuwage/model.py
index 9e206db..044ba27 100644
--- a/pyaccuwage/model.py
+++ b/pyaccuwage/model.py
@@ -6,6 +6,7 @@ import pdb
 class Model(object):
     record_identifier = '  '
     required = False
+    record_length = 512
 
     def __init__(self):
         for (key, value) in self.__class__.__dict__.items():
@@ -52,9 +53,10 @@ class Model(object):
                  custom_validator(f)
 
     def output(self):
-        result = ''.join([self.record_identifier] + [field.get_data() for field in self.get_sorted_fields()])
-        if len(result) != 512:
-            raise ValidationError("Record result length not equal to 512 bytes (%d)" % len(result))
+        result = ''.join([self.record_identifier] + 
+                        [field.get_data() for field in self.get_sorted_fields()])
+        if len(result) != self.record_length:
+            raise ValidationError("Record result length not equal to %d bytes (%d)" % (self.record_length, len(result)))
         return result
 
     def read(self, fp):