There are two types of gaff: one is a large hook used by fishermen to land large fish. We don’t advocate the use of this type, at least not on this site.
The other is an undergarment, rather like a woman’s thong panty, but with a little extra support to keep everything securely in place while creating a smooth female line. Designed expressly for crossdressers, gaffs are available at many T-friendly stores. As with the control panty, Bill and the boys head south for a spell, then you pull the gaff up snug. Fit is important, of course, or things can get out of, er, hand. Because it’s designed like a thong, you can wear a gaff under almost anything, and panty lines are rarely a problem. If the thought of wearing an exclusively male garment while dressed puts you off, remember that gaffs are also available in satin, lace and lots of other feminine-looking styles.