Using the back button on your browser may cause trauma. Best to use "back to shopping" to add more items. To change the quantity click in the box and type the number you want then hit "update cart." After 20 minutes you may time out. If that happens log back in and hit "view cart" and you can continue. You can also call in orders to 877-769-8800 10 am to 5:30 pm east coast time.