Timberline Flexible Panels are built into the skirt of the saddle. They seem fairly stiff when new, but soften up as the saddle is broken in. They come in three sizes; Western, Endurance and English.
The Western Panels come in three styles; Square, Round, and Paso. The length of the panels from the front to the back of the horse can be changed to accommodate shorter or longer backed horses.
For the Paso Fino, Icelandic, or other smaller breeds, we recommend a maximum length of 25 inches. You should not go shorter than this unless the saddle is very small, such as a 13 inch seat. The Paso Panel was designed to accommodate the smaller barreled horse. It is actually narrower than the Endurance Panel and does not push out under your leg when riding a smaller type horse. Because the panel fits 1 1/2 to 2 inches over the scapula, a 25 inch panel does not rest on a short backed horses loin area or hit their hip bones.
The pictures below are of the Round Western Panel, Paso Panel, and Endurance Panel, side by side to show the differences in size. The English Panel is not shown, but is smaller yet.