Klein Tools ET900 USB Digital Meter, USB-A (Type A)

No. The ET900 is a USB-A (Type A) meter only, with a male USB-A plug and a USB-A passthrough. For USB-C or micro-USB ports you need a different meter or an adapter rated for the port's voltage and current, since the ET900 is only rated to 3 to 20V DC and 0.05 to 3A.

Yes. The ET900 reads 3 to 20V DC and is listed as compatible with USB-A and Qualcomm Quick Charge ports, so it will follow a port that steps up past 5V. Current measurement runs 0.05 to 3A, so a charger pushing more than 3A is outside the meter's rating.

Below 50 milliamperes the ET900 will not display current, and the screen reads zero even though the port is still passing power. That is expected behavior, not a fault. A trickle-charging or fully charged device, or a low-draw accessory, can sit under that threshold. Measurement starts at 0.05A.

It gives you voltage, current, capacity or charge delivered, energy, and a calculated resistance, so you can tell whether a port is holding voltage under load and how much charge it has actually pushed. Ranges top out at 99,999mAh capacity used, 999Wh energy delivered, and 400 ohms resistance. It stores and recalls up to 10 readings, so you can compare several ports or outlets on one walkthrough.

No batteries. The ET900 draws its power from the USB port being tested, so there is nothing to charge or replace. It will log continuously for up to 1000 hours, with an elapsed timer that runs to 999 hours, 59 minutes, 59 seconds, which covers an overnight or multi-day charge-rate test without touching it.

That is what the cable is for. The meter body itself measures 2.84 inches long, 1.25 inches wide and 0.56 inches high and weighs about 0.069 lbs, and it connects through a durable cable rather than plugging rigidly into the port, so you can get into crowded power strips, under-desk hubs and panel-mounted ports and still read the screen.

The housing is polymer and built to survive a 6.6-foot (2 m) drop, which covers a fall from a ladder step or a bench. Ingress protection is IP20, so it is finger-safe against solid objects but has no water rating. Keep it dry and do not use it in wet weather or during electrical storms.

Different jobs. A multimeter is what you use on branch circuits, receptacles and line voltage. The ET900 is an inline USB-A tester: it sits between the port and the load and tells you what that port is really delivering, which a multimeter cannot do without breaking out conductors. It is rated for 3 to 20V DC and 0.05 to 3A only, so never put it on anything above those limits. Treat it as the tool for proving out charging ports, USB wall plates, power banks and tool chargers, and keep the multimeter for the circuit feeding them.

It has voltage and current overload detection built in, so it flags a port running outside its range. That is a warning feature, not permission to exceed the rating. Anything beyond 3 to 20V DC or 0.05 to 3A should not be connected to it at all, and Klein warns against using the meter if it looks damaged.

The ET900 uses a high-resolution LCD chosen for visibility in low ambient light, so readings stay legible in panel rooms, ceiling spaces and crawlspaces without a second hand on a flashlight.

Order Klein Tools ET900. That is the model and the manufacturer part number, and it is the USB-A (Type A) version of Klein's compact USB meter.