MS8040 22000 Counts High Precision Desktop Digital Multimeter with AC True RMS & LPF & RS232 Data Communication has a wide range of applications in labs, factories, and work rooms. With high resolution for the measurement of voltage and current. The precision of DC voltage and current even reaches up to 0.05%. The MS8040 offers two power supply options and RS232 data communication interface, satisfying all your needs. And it has the low-pass filter (LPF) to effectively reduce high-frequency noise when measuring AC voltage.