I used the zSilver I saved up to spend on the keycap. The code works fine in the store but the shipping cost seems to jacked up when I used the code. It were $25.48 shipping before putting in the code and $25.77 after the code. I know its not much different but $25 shipping for a small, $50 item seems to be unreasonable and that the shipping price differences can varies from item to item. Thought I might report this just in case there is a bug in the system when using the discount code.