The ADK7 deluxe silicone lead is the optimal way to test most electrical parameters you run into during field service. The kit includes the ADSL2 silicone leads and ASA2 alligator leads plus the all new RCT2 "Molex"-style probe tips. HVAC techs often remove the black probe tip (common) and insert the black alligator lead for an extended reach from ground. When used with Fieldpiece stick meters, the Volts (red) probe tip is inserted into the top of the meter for easy one-handed testing. Use both alligator extension to perform "no-hands" tests. Silicone test leads deliver better performance in temperature extremes than test leads insulated with vinyl.