Model 374A is specifically designed to enable the detection of ultralow level, low frequency vibrations associated with very large structures, foundations, and earth tremors. The sensor typically possess exceptional measurement resolution as the result of a comparatively large size, which furnishes a stronger output signal and a lower noise floor. Both ceramic and quartz sensing elements are utilized in seismic accelerometer designs. The 374A with ceramic sensing element, offers the best low frequency response. Build-in low noise signal conditioning circuitry offer the greatest measurement resolution. For the best measurement clarity, seismic accelerometers should be used with a unity gain, battery powered signal conditioner. The accelerometer offer rugged, laser welded, stainless steel housing with durable military style connectors. Electrical case isolation, hermetic sealing, RF, EMI, ESD, and overload protection all ensure tolerance against environmental influence and mishandling. All variations provide reliable measurements and long-term stability