u/BoBgOdS66

If you purchased either of these or both like I did you may have wondered how you could ever get another battery for them. Unfortunately they do not use the same battery as other Ferrex 20V tools, so most online results will not be applicable. I have good news, Ferrex is using the same design as SuperHandy, I took the chance and ordered this from Amazon and the battery fits and works identically, is compatible with the existing chargers I have from Ferrex, and offers 4 amp hours vs 2 amp hours of capacity, downside is it's 50 dollars but if you have multiple tools and want 2x the runtime it may be worth it. I hope this is helpful for someone and prevents one more tool being trashed due to a bad battery.

Ferrex String trimmer and leaf blower battery replacement found