For orders placed online through this Web site, we accept credit cards and debit cards branded by Visa, Mastercard, Discover and American Express. We also welcome PayPal.

To place purchase orders, orders for U.S. government agencies, or orders paid by electronic check, please call us at 1 (866) 472-8346 (toll free in the U.S.) or +1 (215) 848-8000 during U.S. East Coast business hours for further assistance.

The purchase amount for credit card orders is authorized at the time of your order, and typically billed the day shipment takes place. (This may occur the same day.)

This site employs up-to-date security and encryption methods to protect the privacy of your order and your payment information. During the checkout process, most Web browsers will display a "padlock" icon in a corner of the window, to confirm security measures are active.

During checkout, you may elect to save your preferred payment method for future purchases. You may also log in at any time to modify or remove your payment method, either using the link to our Web site found in the order confirmation you receive, or by returning to the checkout area of the Web site, accessible from the shopping cart.