I used those plenty as a kid but it took me a minute to remember WTF they were. I used to dig through my mom's old singer songwriter collection: James Taylor, Carly Simon, Joan Baez, America, et al trying to find something to do after school. We had this huge cabinet TV with a record player on one side.
At around age 10ish my brother and I got a Sony (or maybe Sanyo, not sure) record player/eight track system for Christmas along with Kiss Alive II on vinyl and Lennon Double Fantasy on 8 track.
Unfortunately we did not hang on to any vinyl. I have friends with stacks of records from the 60s and 70s, both singles and albums, that they inherited from their folks.