By clicking into each box, you can enter up to 20 product numbers and their quantities. Using the tab key, you can move the cursor form one box to the next. If you need to change quantities, highlight the quantity number and enter your new desired quantity. Then click the "Add Items to Cart" button below. Once the items have been added to your cart, then you will be presented again with this form to add additional items. Items in your cart can be updated by clicking the "view cart" button.