These go over a record that is in a paper or plastic inner sleeve. These record jackets are perfect for replacing worn out and torn covers for 12" records. They're also perfect for saving your original jackets from ring wear - simply store the record in these new jackets and you don't have to worry about ruining the original and often valuable cover! The dimensions (length being spine to the opening and height being closed edge to closed edge) are 12-1/2" x 12-1/4" (or 317.5mm x 311.15mm).