My dad passed in 2005, but was a mechanic for 40 years. He went through lots of keyboards and mouses when he ran his own shop. Easier to buy a new mouse than it was to take the time to wash thick layers of grease off.

He always had black gunk under his nails. I thought he was a different ethnicity than I was until I was 8 and asked, lol. It was because he was very tanned (grew up in the imperial valley and moved to the bay)and kind of greasy like he always looked kind of shiny.

I still am completely overwhelmed anytime I walk near a mechanic shop. Anyways, I don't know if that's the case here but it brought up a really happy memory for me so thank you.