Thermophore MaxHeat Plus 14 x 27 Large Shampoo Showers Bathtubs 5v instruments heads * Adjustable Color:Red 5v instruments heads * Adjustable rheostat control * Safety switch to prevent accidental draining of battery * Metal head connectors for durability * Direct plug in style * 100 130v 50 60 Hz * Model WA71000C uses 3 Specifications: Weight: 99 lbs Just hold down or press on for heat and release or press off to cool depending on the style *MaxHEAT Plus units let you add additional water in dry environments * Moisture helps the intense heat penetrate even more deeply relieving pain relaxing muscle spasm and increasing rejuvenating circulation * Two switch options put you in total control of the heat level minute by minute