diff --git a/barcodes/attributes/size_attribute_getter.py b/barcodes/attributes/size_attribute_getter.py
index 430cdb4..1d206fb 100644
--- a/barcodes/attributes/size_attribute_getter.py
+++ b/barcodes/attributes/size_attribute_getter.py
@@ -4,4 +4,6 @@ from models import Product
 
 class SizeAttributeGetter(BaseAttributeGetter):
     def get_value(self, product: Product):
-        return product.size
+        if not product.size:
+            return None
+        return f'<font size="8" name="Helvetica-Bold"><b>{product.size}</b></font>'
diff --git a/barcodes/generator/default_generator.py b/barcodes/generator/default_generator.py
index 8e3a133..70b9288 100644
--- a/barcodes/generator/default_generator.py
+++ b/barcodes/generator/default_generator.py
@@ -21,11 +21,15 @@ class DefaultBarcodeGenerator(BaseBarcodeGenerator):
                 if not attribute_getter:
                     continue
                 value = attribute_getter.get_value(barcode_data["product"])
+
                 if not value or not value.strip():
                     continue
                 attributes[attribute.name] = value
             for additional_attribute in barcode_data["template"].additional_attributes:
-                attributes[additional_attribute.name] = additional_attribute.value
+                value = additional_attribute.value
+                if not value:
+                    continue
+                attributes[additional_attribute.name] = value
             barcode_text = '<br/>'.join([f'{key}: {value}' for key, value in attributes.items()])
 
             pdf_barcodes_gen_data.append(
diff --git a/barcodes/pdf/generator.py b/barcodes/pdf/generator.py
index b378305..f5f6b90 100644
--- a/barcodes/pdf/generator.py
+++ b/barcodes/pdf/generator.py
@@ -34,7 +34,7 @@ class PDFGenerator:
             leading=7,
             spaceAfter=2,
             leftIndent=2,
-            rightIndent=2
+            rightIndent=2,
         )
 
     def generate_small_text(self, barcode_value, text, num_duplicates=1):