Car Battery Tester BM310 12V Auto Battery tester with 6 LED Test Lights Display. Battery tester size: 12 5.2 1.8cm / 4.7 2 0.7in. Alternator state check 1 x 12V battery tester. Attach the cable clip of the red cable to the plus point(+）of the battery and the cable clip of the black cable to the minus point(-)of the battery. ).
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