My heritage... well, Swedish for the most part, but I'm pretty sure my paternal grandmother's parents were German (I know her mother was, and I think her father was born in Sweden but had German parents).
I have fine, straight hair that is some sort of light brown colour. When I was a kid I used to call it "caramel coloured" . I had blonde hair as a toddler, but it darkened to a light ashy brown pretty fast.
My mother have fine, very dark brown hair, probably 1a/1b.
My father have coarser (maybe M) hair, that is also a very dark brown colour (almost black), and 1b (when it gets long, it gets kind of wavy). When he was young it was fine and curly and had a whitish blonde colour.
Genetics are weird, since none of us kids got our father's brown eyes, and none of us have dark brown hair.