https://sellout.woot.com/offers/autolite-iridium-xp-automotive-2 4-Pack Autolite Iridium XP Automotive Spark Plugs (XP5325) on sale for $8.99. Shipping is free for Amazon Prime Members (must log in with your Amazon account and select a shipping address in order for Woot to apply free shipping) or is otherwise $6 per order.