We accept credit card and PayPal for all customers.
For educational institutions we also accept purchase orders and pro forma invoices.
After placing the order with a purchase order you will receive instructions by email on how to send us a copy of the PO. Once the PO has been received, we will process your order and send you an invoice. This usually happens within 24 hours. Note that with purchase order a handling fee of $20 will be added to the order if the total excluding taxes is below $200 USD.
With pro forma invoice the invoice will be sent to you after you have placed the order. Once we have received payment for the invoice, the order will be processed. Note that with invoice payment a handling fee of $20 is also added to the order if the total excluding taxes is below $200 USD.