The 4 Step System comes with 4 interchangeable inserts that allow you to customize how Barefoot Science® works best for you – for reduced muscle fatigue

Trimmable to 3/4 length

Narrow Width: Fit Women's A to AAA and Men's B to C

Ideal for recreational

Use only with shoes that HAVE removable insoles

Next Generation Stimsoles® Insoles Standard The 4 Step System comesTransforms your shoes into a therapeutic exercise program for your feet. For all activities: walking, running, and standing. Comfortable, safe, and easy to use. Improves foot, leg, hip, and back problems. Clinically tested and doctor recommended. Unconditionally guaranteed.