Al & Ed's is mainly located in SoCal and they are having a one day sale on saturday (11/26). Everything will be 50% off from 9am to 9pm, but there is a catch....
Here's what the fine print states:
Standard installation MUST be purchased on all items. This coupon must be presented at time of purchase. Limit of one item per vehicle for the 50% off MSRP. Limited to supplies on hand. No special orders. Not valid with any other offer or discount. Excludes window tint, wireless phones, wheels and tires.
I guess they'll find a way to rip you off on the installation process