Instant Heat--Completely Reusable! Designed to Fit on Shoulders and Neck. This (21.5cm x 40.8cm) Instant Multi-Use Neck and Shoulder heat pack is an amazing product to use when heat therapy is required to treat or loosen sore, stiff muscles anywhere on the body. Ideal for therapists, practitioners, all Sports and home users if you need instant heat here is the answer. Our internationally recognized heat packs are for individuals and organizations in the following industries: *Medical *Athletics *Massage *Education *Physio *Health & Fitness Centers *Hotels & Spas *and more Each heating pad is non toxic and can be re-used hundreds of times. Just by clicking the disk in the pad, will activate it and it will reach 54°C within seconds. The pads are safe and non toxic due to the innovative use of the salt based solution, Sodium Acetate. This will remain usable for 30min or more. To reuse just place in boiling jug or pot of water until clear then will be ready to reactivate.