Quadratech's "Sale" price was the same as the other retailers normal price. The other retailer offered free shipping as well. I try to support the retailers on the board, as I feel it's important to the board.
There's no "code", they apply the discount to your quadratec account. I went through the process of doing that and never actually got a discount on anything. They also screwed me over on a Warn Zeon and now I avoid them at all cost.