Features: brand new and high quality SELF-HEATING FEET WARMER. Multi-layer design: non-wavon fabric＋breathable film＋iron powder＋thick protective pad. The temperature is fast heating up by physical reaction between iron powder and oxygen. EASY TO USE. Slef-adhesive design, convenient to paste on your socks. WARM TIPS: Don'for t stick it on your skin directly, avoiding scalding your feet. WARM AND COMFORT. Eco-friendly materials, safe and convenient. 3 seconds quickly heat up. Constantly and evenly heating for time almost 12 hours. Keep your feet warm all day. DIMENSION DETAIL. Male size: 9.8'' x 3''. Female size: 9'' x 3''. The universal feet warmer sticker is also suitable for teens, olds, home, ourdoor walking, hiking, biking, skating, skiing, etc. for IDEAL GIFT. Heating assistant for feet warming in the cilling winter. Wonderful gift for father, mother, grandpa, grandma, friends and children on Birthdays, Christmas, New Year, Thanksgiving, etc. Specifications: Type: Male; Female Color: As Picture Shown Maximum Temperature: 60° Heating Time: 8-12 Hours Male Size: Approx. 250x80mm/9.84x3.15in Female Size: Approx. 230x75mm/9.06x2.95in Material: Non-woven Fabric＋Iron Powder Weight: Approx. 85g Package Includes: 1 Pair Self-heating Insoles note: Not not for infants and pregnants women. Please do not wear it when sleeping. And do not paste on your skin directly. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!