The slot on a floppy drive is just large enough to insert the |diskette|. This minimizes introduction of dust and other foreign objects into the drive. On some models, especially the |5 1/4" format|, the slot features a small latch which closes the drive. The latch may also act as an ejector button and diminishes the risk that the user will inadvertently insert a second diskette into the drive while the first is still in the drive. Doing so can damage the drive's mechanisms or the media. On types without this latch, a diskette ejector button usually is added.