| 摘要 |
<p>The holder consists of a semi-rigid card with a binding margin on the left and a flap on the right. At the edge of the binding margin, three plastics material sleeves (12,13,14) are glued or heat sealed to the card. The sleeves overlap each other and have openings along the edges furthest from the hinge. Disc cassettes are inserted, aperture first, into the sleeves and hinged down onto the card before the dust exclusion flap is folded over. A disc cassette can be extracted from a sleeve using the thumb cut-out on the open edge. The binding margin may have holes punched in it for a ringbinder. The sleeves and/or the card may be transparent or opaque.</p> |
