While the armed forces discourages troops from using commercial portable two-way radios (because they are not encrypted, even if they are other more effective than military gear), there was one off-the-shelf radio that did meet military requirements in Afghanistan. This was the Racal MBITR (Multiband Inter/Intra Team Radio). Weighing only 31 ounces, could handle wide range of frequencies (30 - 512 MHz), Voice and Data and selectable power output (100 mW to 5 W). It was waterproof and, most importantly, had the optional compatibility with military systems (Army SINCGARS SIP and Air Force HAVEQUICK II). The battery gives about ten hours use at maximum power. There is a 32x80 pixel backlit display. Moreover, the radio is programmable, enabling users to create their own options. The manufacturer configured the MBITR to Special Forces specifications, while another firm produced a hands free system (using an earpiece, microphone and cables.) The Special Forces use the MBITR to call in air strikes and communicate with transports and helicopters overhead. The radio plugs into a GPS to allow troops to transmit exact location for the use of smart bombs. The radio also has a beacon function, so that rescue aircraft can quickly find troops using MBITR. The manufacturer worked three years (beginning in 1997) with the military to insure that the military needs were met, and SOCOM bought 8,000 MBITRs, for about $3,000 each.