What was old is new again

I’ve had this ‘modular’ circular saw, my whole life.
I get it from my Dad, but I don’t know where he got it, store, garage sale, maybe his father, my grandfather. don’t remember. but i’ve been hanging on to it on my ‘power saw shelf’ for decades.
you attach a drill to it and, well try to cut a straight line : )

buy this tool on my etsy store, or not. : )