This Klein Tools NCVT1PKIT Non-Contact Voltage and GFCI Receptacle Test Kit includes the NCVT1P Non-Contact Voltage Tester and RT205 GFCI Receptacle Tester, making it suitable for a variety of electrical troubleshooting tasks. The Non-Contact Voltage Tester accurately detects standard voltage in cables, cords, circuit breakers, lighting fixtures, switches, and non tamper-resistant outlets. Additionally, the GFCI Receptacle Tester can detect various wiring problems in standard receptacles.