If you've never used a catalytic hand-warmer while camping, you've never truly been warm.
Good for winter sports or various outdoor works in winter. Preventing any possible physical damages caused by body stiffness due to body temperature drops for outdoor activities such as golf, fishing, skiing, mountain climbing, outdoor visitors, police, soldier, and fisherman. Useful for those suffering from colds, influenza, neuralgia, rheumatism and backache.