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Klein Tools RT210 GFCI Outlet Tester
A three-light plug-in tester for standard and GFCI receptacles that shows common wiring faults and has a button to trip a GFCI.
Comes in 4 versions: see which to buy
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Klein Tools
Klein Tools NCVT1P Non-Contact Voltage Tester Pen (50-1000V AC)
A basic pen-style non-contact AC voltage detector with a 50 to 1000 V AC range, a red LED and tone alert, and a CAT IV 1000V rating.
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Photo: Klein Tools
Key facts
- Detection range
- 50 to 1000 V AC
- Frequency
- 50 to 500 Hz
- Indication
- Green LED when on; red LED and audible tone when voltage is sensed
- Tamper-resistant outlets
- Not recommended by Klein (it points to the NCVT-2P or NCVT-3P in low-voltage mode)
- Won't detect (manual)
- DC voltage or voltage inside shielded wire
- Safety rating
- CAT IV 1000V
- Safety standards
- Conforms to UL 61010-1 and 61010-2-030
Which version should you buy?
This page covers: NCVT1P pen only.
NCVT1P pen only
This pageModel: NCVT1P
- What differs
- Single-range pen for 50 to 1000 V AC, with light and sound alerts.
- Best for
- Basic AC voltage checks without a low-voltage mode.
NCVT2P dual-range pen
Model: NCVT2P
- What differs
- Adds a sensitive 12 to 1000 V AC range alongside a 70 to 1000 V AC range.
- Best for
- Low-voltage AC doorbells, thermostats and irrigation systems.
NCVT1XT protected pen
Model: NCVT1XT
- What differs
- Detects 70 to 1000 V AC and adds IP67 dust and water protection.
- Best for
- Standard AC checks where dust and water protection matter.
NCVT1PKIT pen and outlet tester
Model: NCVT1PKIT
- What differs
- Pairs the NCVT1P pen with an RT205 GFCI outlet tester.
- Best for
- Checking outlet wiring and GFCI operation as well as detecting AC voltage.
Watch out
- NCVT1P and the older NCVT1 are different models; the NCVT1 recall covers date codes ending H7.
- NCVT1PKIT adds an RT205 outlet tester; it is not the pen-only package.
- NCVT2P adds low-voltage AC detection; NCVT1XT starts higher than NCVT1P.
- Klein does not recommend NCVT1P for tamper-resistant outlets.
Why people pick it
- One button, one threshold: simple for occasional use
- CAT IV 1000V rating and a 2 m drop rating
- Green power light shows the pen is on before you rely on it
Know before you buy
- Klein doesn't recommend it for tamper-resistant outlets
- AC only: no DC detection, and shielded cable blocks it
- Silence doesn't prove a wire is dead: test on a known live circuit before and after use, per Klein's manual
- No flashlight or low-voltage mode
Full specifications
| Detection range | 50 to 1000 V AC |
|---|---|
| Frequency | 50 to 500 Hz |
| Indication | Green LED when on; red LED and audible tone when voltage is sensed |
| Tamper-resistant outlets | Not recommended by Klein (it points to the NCVT-2P or NCVT-3P in low-voltage mode) |
| Won't detect (manual) | DC voltage or voltage inside shielded wire |
| Safety rating | CAT IV 1000V |
| Safety standards | Conforms to UL 61010-1 and 61010-2-030 |
| Drop protection | 2 m (6.6 ft) |
| Power | 2 × AAA (included) |
| Auto power-off | Yes |
| Pollution degree | 2 |
From manufacturer documentation, checked November 2, 2026. Spotted an error? Tell us.
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