{ATTACHFILENAME} - The filename on disk of the attached file.
{ATTACHFILETITLE} - The readable submitted file name of the attachment, suitable for display.
{ATTACHDOWNLOADS} - The number of times the attached file has been downloaded.
{ATTACHKB} - Size of attachment in KB.
{ATTACHWIDTH} - The width of image attachments in pixels.
{ATTACHHEIGHT} - The height of image attachements in pixels.
{ATTACHISIMAGE} - Tells if it's an image or not, for use in conditionals.
{ATTACHTHUMBURL} - The location of the thumbnail for an attached image, for use within an <img src> tag to display a thumbnail.
{ATTACHDOWNLOADURL} - The URL to click to download the attachment, for use within an <a href> tag.
-- Optional parameter: direct. {ATTACHDOWNLOADURL[direct]} will give the actual URL of the source image on disk instead of the download.php version.
{ATTACHDATE} - The date/time of the attachment. Accepts usual date parameter.
{ATTACHEXTENSION} - The file extension of the attachment.
{ATTACHFILEPATH} - The path to the file.

Note that attachment variables can be used either in toplists of attachments or within <!-- BEGIN LINK ATTACHMENTS --> areas.