Hokkairo refers to Kowa's brand of body warmers. Expiration Date: 2026.04 ※ The expiration date of the body warmer refers to "the period during which the indicated temperature specifications are guaranteed," not "the period during which the product can be used." Please use with confidence. This is stated on the official website. Made in Japan Kowa Size: 70mm x 90mm Sold in sets of 10. You can simply think of it as a 10-day supply. This is the "insert in shoes" type!!! Maximum temperature: 41°C Average temperature: 35°C Maintains a stable temperature for 7 hours! Excellent heat retention, a warm body warmer anytime, anywhere. Thin and non-slip. Instant purchase is welcome!