public function createPackage()
    {
        if (!$this->getTransactionID()) {
            throw new MissingTrackingParameterException('transaction id is missing');
        }

        if (!$this->getName()) {
            throw new MissingTrackingParameterException('item name is missing');
        }

        return array(
            't' => 'item',
            'ti' => $this->getTransactionID(),
            'in' => $this->getName(),
            'ip' => $this->getPrice(),
            'iq' => $this->getQuantity(),
            'ic' => $this->getSku(),
            'iv' => $this->getCategory(),
            'cu' => $this->getCurrency()
        );
    }