diff --git a/htdocs/expedition/class/expedition.class.php b/htdocs/expedition/class/expedition.class.php
index 915177164ac..1a9a249effc 100644
--- a/htdocs/expedition/class/expedition.class.php
+++ b/htdocs/expedition/class/expedition.class.php
@@ -325,8 +325,8 @@ class Expedition extends CommonObject
 		$sql.= ", ".$this->sizeS;	// TODO Should use this->trueDepth
 		$sql.= ", ".$this->sizeW;	// TODO Should use this->trueWidth
 		$sql.= ", ".$this->sizeH;	// TODO Should use this->trueHeight
-		$sql.= ", ".$this->weight_units;
-		$sql.= ", ".$this->size_units;
+		$sql.= ", ".($this->weight_units>0?$this->weight_units:'NULL');
+		$sql.= ", ".($this->size_units>0?$this->size_units:'NULL');
 		$sql.= ", ".(!empty($this->note_private)?"'".$this->db->escape($this->note_private)."'":"null");
 		$sql.= ", ".(!empty($this->note_public)?"'".$this->db->escape($this->note_public)."'":"null");
 		$sql.= ", ".(!empty($this->model_pdf)?"'".$this->db->escape($this->model_pdf)."'":"null");