Bests & Worsts Reviews from Amazon

This battery IS NOT a 5.0Ah battery. Though I'm an electronics engineer, it wont take a rocket scientist to understand what I'm going to explain. I have a 3Ah battery from another manufacturer and it works great in my weed wacker -- cutting faster than any gasoline weed wacker I have ever owned, over decades, but it doesn't last very long because the 3Ah battery sends maximum power to the weed wacker motor (which I think is also great because I want to get done faster). Who doesn't want to get done faster by using a more powerful machine? So, to get more run time (before recharge) I bought this 5Ah battery that I'm saying really isn't a 5Ah battery. Yes, it runs much longer -- in fact, over twice as long. But that's because it is sending less current (and therefore less power) to the weed wacker's motor. This is a huge problem with me because I have to spend much more time cutting the same amount of weeds because less power is getting to the weed wacker's motor. How do I know that this battery IS NOT a 5.0Ah battery? Because this battery that I am complaining about weighs less than my 3Ah battery. An Ah (Ampere-hour) rating is an energy rating. To deliver more energy, and thus do more work, a battery of the same technology (in this case Lithium-ion) must weigh more: a 5.0Ah battery must weigh five-thirds (5/3) more than a 3.0Ah battery. This battery does not do that. My "trusted" 3.0Ah battery weighs 49.1oz. This battery I am complaining about weighs 45.4oz. In other words, if my trusted 3.0Ah battery is used as a standard, this "5.0Ah" battery contains less energy than my 3.0Ah. If you want to pay more for less ... go right ahead. Summary: I have a shipping scale which can measure things to a fraction of an ounce -- there are 16-oz in a pound: __As I wrote above, the "5-Ah" battery I am complaining about weighs 45.5oz. __My trusted 3-Ah battery weighs 49.1oz. __A 4-Ah battery from the same trusted manufacturer weighs 64oz (now that's what I'm talkin' about!). Note: when you see a weight number for something you are buying at Amazon, that's virtually always a shipping weight. It is not item weight. When you want to know an item weight, the best way to accurately get that is at the manufacturer's web site.