Thank you for supporting the Commander X16 project!
Standard purchases cannot be made along side your pre-order. If you wish to order items not related to the Commander pre-order you will need to place a separate order. If you add standard items to your cart while your pre-order is awaiting checkout, your cart will be emptied.
Only one Pre-Order is allowed in the cart at a time so be sure to make all your selections and quantities here before adding to cart.