ADJUSTABLE SADDLES These are saddles that have adjustable gullets. They are very useful for changing the shape of the wither area when the horse gains and loses weight. The Perfect Fit Saddle Fitting Kit is very useful to use on these saddles. After establishing that the saddle fits, the checks that you make on the horse's shape will tell you if the gullet needs changing and, when it is changed, if you've chosen the right gullet size for your horse by checking that it then fits the horse properly.
Bates Wintec have recently brought out a saddle that allows you to change not only the shape of the wither, but the shape of the rest of the saddle. Again you can use The Perfect Fit Saddle Fitting Kit to establish whether the saddle needs adjusting and to check it when you have adjusted it.