Spenco Incorporated (a) Spenco Standard Full Insoles #4 - W 11-12.5/M 10-11.5 - The Spenco RX Comfort Insole provides increased shock absorption to help tired feet and protect against friction and blisters. The thin, flat design provides additional lightweight cushioning when paired with cushion custom orthotics. The full-length design provides heel-to-toe comfort while Spencore material offers a cushioning layer that absorbs shock and impact to provide additional comfort. The top layer of the insole is made with a 4-way stretch fabric that prevents blisters and controls odor with Silpure. Available in seven sizes to help you find a better overall fit, the RX Comfort Insole also comes with a one-year unconditional guarantee. To use this insole, simply place it in shoes with the green side up. Trim with scissors as needed for best fit. For care, the insole may be hand washed in warm water and air dried.