Summit Racing Coupon Codes: 10% off $75+, 15% of $150+, or Free Shipping on $25+ through 12/17.
XS1210 = 10% off $75 or more.
XS1215 = 15% off $150 or more.
XS12FS = Free Shipping (domestic ground) on orders of $25 or more.
Summit Racing does this once a year and it's usually only 10%. Unfortunately, the codes are NOT stackable.