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

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

Ideal for recreational and leisure activities

Interchangeable inserts allow the user to personalize the arch stimulus strength and choose the sensory experience that feels best

Thin and comfortable – designed to enhance the stimulus properties of our amazing footwear

Wide Urban Flex Sneakers - Sapphire Narrow The 4 Step System comesIdeal for everyday wear, recovery, and relaxed movement. Wide Width: Fits Women's D to E and Men's EE to 4E