TRUSTECH Ice Maker 9 Bullet Ice / 8 Min - Highly Efficient Ice Machine, Auto Cycle Working, Auto Shut Off, S/L Size Bullet Ice Cube Ice Maker Machine with Ice Scoop and Removable Bucket, 26 lbs/24h

Hunters and Construction workers Use these nifty objects throughout the winter months to keep warm in cold weather. What is the science behind these handy items?... ...This "hand warmer" heat pack contains a super saturated solution of water and sodium acetate. Snapping the metal disc creates chain reaction causing the solution to crystallize. The crystallization process gives off heat. The heat packs can be recharged back to the liquid state by boiling water for 10-15 minutes and allow it to slowly cool. Reusable over and over again. Comes with Teacher's Guide. Buy two, one for each glove on those COLD winter mornings! Also available in a larger 8 x 8 size with a Teacher's Guide.