3.8 inches x 10.3 inches. Deep penetrating heat. From the makers of Tylenol. Air-activated heat therapy. Targeted relief for muscle and joint pain. For back and body. Lasts up to 8 hours. Individually sealed patches. Easy application. Odorless, no mess. Does not contain acetaminophen. Precise Pain Relieving Heat Patch: Its pain relieving heat penetrates beneath your skin. You can target the relief right where it hurts. Made in Japan.