Liner has panels of Ultra ThinLine sewn on top with pockets to add shims for minor saddle fitting needs. Shims (sold separately) should be used only as needed. Improve Rider Equitation, Proven the most effective saddle pad for increased communication between horse and rider. Easier to sit and ride the gaits while giving an ultimate close contact feel. Plenty of Protection under the saddle for you and your horse but with only 6mm at your leg. The soft supple felt lies perfectly on horses with all back and wither types. Easy to trim for shorter saddles, use under your how pad. This pad measures 31" long by 30" wide.