Review on 12V Car Digital Voltmeter Gauge by Joshua Follansbee

Update - I bought a second unit and its readings are low compared to the first unit. I saw a comment from another reviewer that it was low for him and now I understand. So test it with an accurate gauge and maybe the seller can replace it. I was busy when this happened so I missed the return window. Below is my previous review. end of update. Added to an aging car, sure to save almost $1,000 on unnecessary repairs. I chose SMAKN even though it's twice the price, emits less light, and requires twice the operating current at 35mA. Got this for a son who drives a 25+ year old car that works fine most of the time. His performance was poor and the mechanic tried to sell him a generator and distributor "which installed for only $1,000." But it was consistent with my previous experience with this machine over the years where we were sold an alternator to ostensibly fix a run out. But the car and alternator tester showed that the "new one" worked just like the supposedly bad one we had. And it had absolutely nothing to do with fixing the problem the mechanic eventually discovered. So this time we installed the $66 manifold ourselves in less than 30 minutes. I installed this LED meter in 15 minutes for less than $20. We've saved over $900 on repairs, including over $600 by eliminating unnecessary alternator changes. Now my son can see "14.2" when he moves and "12.5" or so when he sits in the light. Look at the photo where I have two DMMs and this device, all at the same voltage, with a SMAKN that is about 0.1 volts lower. I told him that since the voltage is in the 13.8-14.5 range most of the time at high idle or when driving, you don't need an alternator. Below 13.8 the battery won't survive and you can compensate by charging overnight. Above 14.5 and you may need to add more water. The battery is 3 years old and out of warranty so I installed an alligator clip to release when parking. It's "only 35mA," but that's almost half a watt and could speed up the day he needs to buy his next battery. So a star deduction for low brightness at high operating current. The wires were almost adequate length, stripped and tinned, but a bit short in most cases. But it worked for my tape and alligator clip setup.