I bought an OSC 18 without batteries. The tool itself says to only use BP 18 batteries with it. I can't find a list of those of if other batteries also now work. Can someone point me to a list or explain this?

Does that mean the BPC 15 that is part of the drop down box of alternatives on that page, also works? Sorry if I'm being thick. I don't mind buying more batteries but more importantly don't want to ruin this tool by using a wrong one.

Any 18v battery from festool will run the tool just fine.

I’m very surprised to read the above post stating the 15v won’t work. Festool have always previously been VERY good with backwards battery compatibility in newer tools.

Any 18v battery from festool will run the tool just fine.

I’m very surprised to read the above post stating the 15v won’t work. Festool have always previously been VERY good with backwards battery compatibility in newer tools.

They are probably afraid of people using it with '15V' battery with seriously degraded performance, others using / seeing that low performance without realizing it's performance is .... due to old 15V battery, then not buying the tool. As in; it's bad marketing for Festool.

They should have ditched the whole 15V much earlier. In ~2012 they sold their impact driver only in 15V, also in sets with a T15+3. And the jigsaw was sold in sets with a T18+3. Made no sense whatsoever.