Make 'add to basket' button add 2 items at once

[all your base are belong to us]

I have an uncoventional installation of OS commerce...

 

basically none of the products or info are database driven. I have a custom designed page with links that add items to cart.

 

To add to cart, I have this code:

 

<td><?php echo tep_draw_form('cart_quantity', tep_href_link(FILENAME_PRODUCT_INFO, tep_get_all_get_params(array('action')) . 'action=add_product', 'SSL')); ?>

 

<div><?php echo tep_draw_hidden_field('products_id', '103') . tep_image_submit('cart.gif', IMAGE_BUTTON_IN_CART); ?></div>

 

That little code draws 'cart.gif' from includes/languages/english/images/buttons and makes it appear as a link that adds item 103 to the cart.

 

My question is how can I get that code to make two items go to the card, for example I have a base item that can have 10 different colors. I don't want to have to make 10 products in the cart, i.e.

 

base product - color 1

base product - color 2

base product - color 3... etc

 

etc... Instead I want it to add 2 items to cart

 

1x base product

1x color 1

 

So the question is very simple, how can I get that one button to add two (or even more if you want to give me extra love) products to the cart at the same time?

 

Muchas gracias!