The Fieldpiece EHDL1 Electronic Handle converts any Fieldpiece accessory head into a standalone instrument . The Fieldpiece EHDL1 features a MAX/MIN button to record the highest and lowest reading. A HOLD button to hold the reading. The Fieldpiece EHDL1 has a 200 and 2000 mVAC for use with our Amp Clamp, model ACH4 and the 200 and 2000mVDC range is for use with the rest of our accessory head instruments.