Passing quantity Values to whmcs

[northgate]

Hi

 

I'm offering a product based on quantity I've set up a landing page to promote the product I would like to know it is possible to have the user enter the quantity value on the landing page then pass it to whmcs cart for billing?

 

For now I've simple used a direct link provided by whmcs to the product.

 

If there is any other way to get this done please let me know.