Profoot Ultragel Women's Massaging Insoles Profoot Ultragel Massaging Insoles features 2 layers of gel to provide amazing comfort as well as pain relieving orthotic support. The double gel design actually returns energy with every step, so you'll feel less fatigue & pain no matter what shoes you wear. Blue Gel Layer: Provides comfort & shock protection. Red Gel Layer: A firmer gel that supports the heel & arch in a stable, healthy position to greatly reduce the possiblility of missteps & injury. Profoot Ultragel Women's Massaging Insoles fits women's shoe sizes 6-10. Directions Test for fit. If needed, use trimming guide on underside of each insole for custom fit. May be used in place of existing insoles.