PowerSafe jumper cables take danger out of playing with electricity | CNET Reviews
via reviews.cnet.com
The PowerSafe jumper cables look like your standard jumpers, with a pair of terminal clamps on each end. However, midway through the cables' length is a small electronic brain that monitors the state of the connections and only lets power flow when everything is hooked up just right. So, if you accidentally connect your cable backward on either end, the system will display a red warning light and the power stays off. If you accidentally touch the loose ends of a live cable, the red light glows and there are no sparks. If there's a short of any kind, even within the dead battery, the red light glows and everyone remains safe.
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