Klein Tools 69133 Continuity Tester

No. The 69133 is a power-off tester only. Klein's own warning is explicit: do not use it for checking continuity on live circuits, and wear approved eye protection when working. It works by sending current from its own AAA battery through the circuit and lighting the bulb in the handle when the path is complete, so the circuit has to be de-energized and isolated first. If you need to verify voltage is present or absent before testing, you need a voltage tester or multimeter, not this.

The lead runs 36 inches (914 mm) and ends in an alligator clip, so you can clip one end to a terminal, ground, or one end of a run and probe with the other hand. Overall the tool measures 43.75 inches (111.1 cm) end to end, which is the 36 inch lead plus the handle and probe. Three feet is enough to work within a panel or a control cabinet, but for a long branch circuit you will be clipping to one conductor and walking the probe, not spanning the run.

No battery in the box. The 69133 runs on one AAA, and Klein ships it without one, so pick up a AAA before the tester goes in the truck. The bulb IS included, and both the bulb and the battery sit inside the handle behind a removable nylon cap.

Klein Cat. No. 69131 is the replacement bulb for the 69133. Unscrew the nylon cap at the end of the 4 inch handle to get at the bulb and the AAA cell. If the tester stops lighting on a known-good circuit, swap the battery first, then the bulb.

Finding shorts and open circuits in de-energized equipment: fixtures, switches, receptacles, motor leads, thermostats, control wiring, fuses, and low-voltage runs. Clip the alligator lead to one end, touch the probe to the other, and the bulb in the handle lights if the path is complete. It is a go/no-go tool, not a measuring instrument, so it tells you continuity or no continuity and nothing about resistance in ohms. For troubleshooting where you need a number, a multimeter is the right tool.

The pointed probe is 3-3/4 inches (95 mm) long on a 4 inch (102 mm) handle, so you get most of a foot of reach with a fine point at the end. That gets into a deep 4-square box, behind a terminal block, or onto a screw terminal without pulling the device. The point is sharp enough to bite through light oxidation on a terminal, which is why the eye protection warning matters.

The tester weighs 0.21 oz (6.0 g) and the handle body is about 1 inch across, so it is pen-sized and disappears in a pouch pocket. The 36 inch lead is the only bulky part; most techs coil it around the handle. For an MRO cart or a service van where a continuity check comes up a few times a week, it takes up almost no room.

Klein Tools catalog number 69133, sold as a single tester. The only related number on the family is 69131, which is the replacement bulb, not a tester. Order 69133 for the tool and 69131 when the bulb burns out.