UNI-T is your testing specialist.
Since1988, Uni-Trend Technology (China) Co., Ltd has been the developer, manufacturer and marketer of reliable testing, measuring and inspecting products to over 100 countries and regions globally.

What you get / UT501A
1 x UT501A insulation resistance tester
1 x test leads (pair)
1 x alligator clips (pair)
1 x elastic strap
1 x user manual
1 x packaging box

What you get / UT502A
1 x UT502A insulation resistance tester
1 x test leads (pair)
1 x alligator clips (pair)
1 x elastic strap
1 x test probes (pair)
1 x user manual
1 x packaging box

Specifications / UT501A
Insulation resistance (Ω)
Test voltages. 100V/250V/500V/1000V.
100V. 0MΩ~100MΩ.
250V. 0MΩ~5GΩ.
500V. 0MΩ~5GΩ.
1000V. 0MΩ~5GΩ.
Load current. 50V (R=50kΩ) 1mA/100V (R=100kΩ) 1mA/250V (R=250kΩ) 1mA/500V (R=500kΩ) 1mA /1000V (R=1MΩ) 1mA.
Short-circuit current
AC voltage (V). 30V~750V

Specification / UT502A
Insulation resistance (Ω)
Test voltages. 500V/1000V/2500V
500V. 0MΩ~5GΩ
1000V. 0MΩ~5GΩ
2500V. 0MΩ20GΩ
Load current. 50V (R=50kΩ) 1mA/100V (R=100kΩ) 1mA/250V (R=250kΩ) 1mA/500V (R=500kΩ) 1mA/1000V (R=1MΩ) 1mA/2500V (R=1MΩ) 1mA
Short-circuit current.
Low resistance (Ω). 0.01Ω~200Ω (about 5.0V/200mA)
AC voltage (V). 30V~600V
DAR. 60s/15s and 60s/30s.
PI.

More features
Display count. 2000
Auto range.
Low battery indication.
LCD backlight.
Light alarm.
Buzzer alarm.
High voltage indication.
Over load indication.
Auto discharge.
Test voltage secondary display.
10MΩ internal resistance test.
Power. 1.5V battery x6