You may use a P.O. only if you are a school.

To use a PO, once you have completed all of the details on your order, click "Pay by P.O".  You may then email your PO to us at  We will then invoice you. We cannot fill your order until we receive your PO. Our terms are net 30 and there will be a 20% penalty for any invoice not paid within 30 days.