The Suntoucher is Tread & Butters new low arch, low volume insole. Using the same construction and materials as our flagshipCascadiainsole, the Suntoucher is 30 percent lower volume in the heel and arch, while maintaining the same amount of cushioning and support. If you have a low arch, or a sensitive arch, or proverbial flat feet, the Suntoucher is the one.