Can I return a tool that I purchased three days ago. The tool is a Milwaukee 6 1/2 cordless saw I did use it but the tool was not what I expevted. It had a hard time cutting through a 4*4 pressure treated post Which is something I do an a daily base

Friedman's has always been understanding in my experience

Probably. I've been told by their folk I can return stuff if I have any problem with it.

Call them or take in and ask them

I suspect they'd have a view on that. It has been used so will need cleaning and I'm sure the blade finish has witness marks - and I bet the packaging has gone! And the reason for return isn't that it is defective. Give them a call: they have been known to help out in the past.

Take it back. However maybe a different blade ?

I think you can