Amazon offers the Stok Unsweetened Caffeinated Black Coffee Shots 264-Pack for $27.55. Check out via subscribe & Save to drop it to $26.17. With free shipping, that's the lowest price we could find by about $8. Each shot contains 40mg of caffeine and it's recommended you drink no more than two shots per day.

Note: Be sure to cancel Subscribe & Save after your item ships to avoid being billed for future shipments.