40V 6.0Ah Replacement Battery for Kobalt 40V MAX Lithium Ion Battery KB440-06 KB240-06 KB2540C-06 KB640-03

Just as it says. Would definitely recommend

Battery looks ok on the outside but feels a bit light compared to an oem. Opening it showed the 18650 cells to be unbranded and what information I have found on them they are reported to be under performing. The battery was fully charged when I received it but has since taken a charge and works with my charger. Time will tell on how long it will last. For now at least it seems to be close to the performance of my original battery and the performance of it seems to be on par without any noticeable difference in power. The battery fit into my tool just fine clicking into place without coming loose or seeming loose in the slides. Overall compared to how much the oem batteries are I would definately say that this battery is great value for money.

Works great !! What a value

The Replacement Battery is a great choice and feels almost identical to the name brand in both weight and build quality. If you have ever purchased off brand batteries online you know that many times the advertised amp hours can be a little exaggerated, often being 1 or 2Ah lower than listed. Even with that in mind this battery delivers.I tested it on my Kobalt weed eater and immediately noticed the difference compared to my smaller 2Ah battery. It ran for a much longer time without fading in power and held up well during continuous use. Charging it from completely empty to full was smooth with no issues, and it reached 100 percent without overheating or losing capacity. Good power and fit.What makes this such a great buy is the value. Even if the actual amp hours end up being slightly off, the performance is more than enough for most yard tools, and the cost is a fraction of what you would pay for the name brand at a hardware store. For anyone looking to save money without sacrificing much in performance this battery is definitely worth it.

I have a whole collection of Kobalt 40V yard tools that I love, but after a few years of heavy use, my original batteries were definitely showing their age and not holding a charge for very long. The price for official OEM replacement batteries was steep enough that I was almost considering switching tool systems. I decided to take a chance on this Surpowtec replacement battery first, and I'm so glad I did. Right out of the box, it clicked perfectly into my string trimmer, leaf blower, and the original Kobalt charger with no issues. The fit is just as snug and secure as the original. The real upgrade is the 6.0Ah capacity, which is a significant jump from my old 4.0Ah batteries. The extended runtime is immediately noticeable; I can now edge, trim, and clean up the entire yard on a single charge, whereas before I'd often have to stop and swap batteries. It delivers consistent, strong power without any fading as the charge depletes. This battery is a fantastic, cost-effective way to breathe new life into an expensive tool collection.

This worked great in my weed whacker- give it a quick charge-up no problem, easy installation just slid right in, and I was off and whacking. 2 year warranty which is adequate, quick charging and long lasting, incredible value compared to a retail K0balt battery, does not give you sticker shock.

Reviewing Surpowtec 40V 6.0Ah Replacement Battery for Kobalt 40V MAX Lithium Ion BatteryThis is an excellent replacement for my aging Kobalt 40V batteries.I was slightly concerned about the 6 amp-hour rating on this battery, since when I purchased my blower Kobalt only offered 2 and 4 amp-hour batteries. In theory, dropping a 6-amp battery into the tool should have no effect (other than the tool's running 3 times longer than with a 2 amp-hour battery), and I'm happy to report that this battery performs as expected. The blower pumps out 110 mph air with either battery.Unexpectedly, this battery weighs only a few ounces more than my old 4 amp-hour battery, so I can hardly tell which battery is in the blower -- good to reduce fatigue.The dimensions of the new battery are spot on, and the battery fits just as snugly into the tool as the original battery. They even nailed the Kobalt blue color.All this at a price point about the same as a 4 amp-hour battery!The only negative is that these replacements seem to have fewer vent holes on the side of the battery. Since the battery fits snugly in the compartment of the tool, it's difficult to see how in practice this could make much of a difference in keeping the battery cool since there cannot be much air flow anyway. In my testing, the battery did not overheat, but just possibly heat buildup could occur during very long continuous usage.

This battery pack has 20 18650 cells with each being 2000mAh (or 2.0Ah). Since this is a 10s2p battery pack, that means the actual capacity is 2x2000mAh or 4.0Ah. This is not the 6Ah as stated in the listing.That being said, most knock off tool battery manufacturers on amazon lie about their actual capacity so I wasn't very surprised here. I am annoyed that amazon does 0 to combat this though.The rest of the battery seems to be built well enough, better than some knock off batteries that I've purchased. I've not tested/used it thoroughly enough to tell how the rest of it works and to see if other flaws are present with the charging and discharging circuitry. I will update this review later when I have that information.