This is the Texas Instruments LM386N1 low voltage power amplifier which is available in a DIL-8 package. The gain is internally set to 20 but the addition of an external resistor and capacitor wil allow the gain to be set anywhere between 20 and 200. The LM386 is a power amplifier designed for use in low voltage consumer applications such as AM-FM radio amplifiers, intercoms, tv sound systems, line drivers, ultrasonic drivers, small servo drivers and power converters.