SAR (specific absorption rate) is an indication of the amount of radiation that is absorbed into a head whilst using a cellular phone, the higher the SAR rating the more radiation that is absorbed into the head.
A SAR value is a measure of the maximum energy absorbed by a unit of mass of exposed tissue of a person using a mobile phone, over a given time or more simply the power absorbed per unit mass. SAR values are usually expressed in units of watts per kilogram (W/kg) in either 1g or 10g of tissue.
Mobile phone users should check the SAR value of a mobile handset before purchase. The Specific Absorption Rate (SAR) value has been brought down to a revised 1.6 watts per kilogram (W/kg) from the earlier 2 W/kg. The lower the SAR value the lower is the radiation the phone emits, which is recommended.