Lasts over 8 hours! Ideal for outdoor events, winter sports, commuters, bird watching, camping, golf & more! All natural ingredients, biodegradable; odorless, clean, dry, non-toxic and non-flammable; long lasting heat therapy for poor circulation or joints. package includes 2 warmers. Sold with a custom logo printed directly onto the package;. Complies with FDA, Prop 65. 6.25" W x 4.5" L