Additional 10% of code is right on diet direct website. You can use it on the 2 week plan which is already discounted on sale and actually gives you a few more things than the 4 week. (order two 2 weeks if needed.)
If you only add one 2 week plan, just make sure to add another box of something to bring it to $150 prior to sales. This adds another 10% off.
I was able to get 2 weeks and a box of 7 pretzels for $134