Vinyl Singles With A Pushed-Out Centre
Pop the middle out, or buy a plastic spider.
British 45s came with a removable centre for jukeboxes, and everyone had a drawer full of the little plastic bits.
American singles had a big hole, British ones had a small hole with a snap-out centre. If you popped it out you needed a spider adaptor, and if you lost the adaptor the record was useless on your player.
The centres are collectable now, which would have astonished anyone who ever hoovered one up.
Cost back then
6/8 a single
Goes for now
£3–£300 depending on the record