This is the best CAT5/6 cable tester I could find in this price range. I couldn't find another cable tester (except for an older model similar to this one but with a basic non-color LCD screen) that could determine cable length and fault distance that costs less than $500. ensures that all cables are connected in the correct order. It also tests the outer shield - if continuous - and that was important to me because I was using it to test a newly installed shielded CAT 6A cable. The cable length calculation is quite far from what is expected. Box but easy to calibrate. Unlike the older model, this model has a built-in rechargeable battery (including a micro USB cable and USB charger) and appears to be used to save settings. It can store multiple cable length calibrations (which unfortunately can't be named, they're just numbered), although after power cycling the device it doesn't automatically load the previously used length calibration and you'll have to load one of them manually. previously saved. This is one of the few downsides of the device. I haven't tested RJ11 or coax cables with it yet, but if you want to test standard cable/satellite TV cables you'll need an inexpensive BNC plug and F-jack adapter as the main and remote units are BNC (bayonet ) to have. female connectors.