See the Group Buy BMS Group Buy - #6 by neliuszeeman
You get different models. I currently have a 100A model. The group by is for a 200A model. But there are 20A, 40A, 60A, etc. These BMS are very customisable. You can limit the current in the settings to any value (less than the model limit). So my 100A model is currently set to only change up to 50A and discharge up to 60A even though it can handle 100A.