Record

摘要

A record (12) comprising a convex protrusion (12a) at its center, one or more protrusions (12b) extending perpendicularly from the plane of the record at its circumferential edge, and a recording area between the center and the circumferential edge. The protrusions engage similar indentations (3b, 3e) formed in a turntable to facilitate centering and holding the record for playing and to prevent rotational slippage.