The original battery on our Dyson DC58 Max died after about 8 years. This replacement has about 5 times the capacity. It was easy for me to install with a bit of guidance from YouTube. The battery works perfectly and it is great to have the larger capacity - it means that our cleaning is rarely interrupted by empty battery stall. The new battery is thicker by about 15 mm, so the machine was tending to tip forward when charging or waiting on the bench. I fixed this by taping a piece of wood to the underneath of the dust canister with doube-sided tape. (You could achieve the same outcome by resting the canister on a small block of wood or a book.) For us, the value of the extra capacity far outweighs the minor aesthetic challenge of the thicker battery. We have a super battery and the price was lower than the smaller-capacity branded replacement.