JOAUIAX Non-Contact Voltage Tester,Electrical Voltage Detector Pen Null/Live Wire Tester Breakpoint Finder Voltage Measuring Tool with Dual Range AC 12V/48V-1000V,Buzzer Alarm,LED Flashlight-JMT03

Bought this as removed an extractor fan and a thick cable was left behind, needed to test if it was live or not before cutting it away. This gadget performed exactly as I had hoped! Really great and handy device for testing for live wires etc. It comes with batteries and is really straightforward to use. It has a loud beep that increases with speed the closer it gets to a live voltage/current being picked up. Great job!!!

Nice product and build quality, looks like it will last. It also has a sensitivity button which allows you to find live wires at a further distance rather than touching the wire. Comes supplied with battery’s too so you are ready to go! Very easy to use and is essential when working with electrics for safety reasons.

Was easy to use accuracy was good.

Only complaint would be the sensitive option is very sensitive, but I don't need it for that, and it does exactly what it should do and tells me if a circuit is live. Brilliant for the money. Probably not sturdy enough to leave lurking at the bottom of a toolbox.

Brilliant little pen, great for testing all your wiring, with a good loud beep on it as-well.Was good when I was changing my light switches over to smart switches and also new lighting I put in. With great delivery, ordered 11pm and received about 11am the following day.

Bought this to test power was off in a 230v domestic lighting circuit whilst changing the switch. In low sensitivity mode it failed to register when the power was on even when held right against the terminal. In high sensitivity mode it registered power even when it was off. In fact it registered just holding it in the middle of the room away from any mains power.

Used for tracing live wires. Worked perfectly. Well pleased

When you first receive this, it is understandable if, like me, you initially viewed this as a cheaply made and therefore very likely to be a prone to errors voltage tester. The packaging is nothing fanciful and the device itself is made of plastic. Weighing 35g without batteries, this non-contact voltage tester measures 16cm long and has a diameter of approximately 2.5cm. It’s blue and is like a thick pen. It even has a pen pocket clip.It is supplied with 2 x AAA batteries that are easily fitted to the bottom end of the tester. The tester has 3 buttons - on/off, flashlight and sensitivity.Using is straight forward - point in the general direction and the unit should beep and indeed it does. With the sensitivity button off, and one you approach current the tester beeps and flashes red. Pointing it at the kettle cable, sometimes it flashed and beeped but very worryingly, some times it did not. This I encountered when pointing at thicker insulated cables. With thinner wires, such as phone charger, it worked perfectly well. Pointed at a 3 pin plug, it worked well enough and the beeping gets faster the closer you get. For thicker cables, I found myself pointing at various different parts to make sure.The other problem I encountered with this unit is when the sensitivity button is on. For some inexplicable reason, the unit will beep and flash red even when you are nowhere near any current. Very odd. It will though flash red as you approach a live current which is exactly what it is supposed to do. You are then advised to switch from high to low sensitivity. But my concern is the unexplainable beeping in the high sensitivity mode.The flashlight is a useful feature.I’m summary, this unit is capable of confirming whether a wire is live but there are inconsistencies. Is it a professional device - no. Is it a device you will depend on - no. Is it a device that will help determine current - yes. If it doesn’t detect a current will I trust this device - certainly not. It is not a device i feel that I cannot trust, unless I’m certain I’m not exposing myself to an electric current. Electricity is not to be toyed with.