Walmart offers the Salonpas Pain Relieving Patch 20-Pack for $3.88. Opt for in-store pickup to dodge the $5.99 shipping charge. That's tied with our January mention as the lowest price we could find by $4. Each patch measures approximately 2.8" x 1.8" and purports to relieve pain for up to eight hours. They contain camphor, menthol, and Methyl Salicylate.