2UNDR Swing Shift Boxer Brief Size:XXLarge ● Ideal for relieving tightness

● Ideal for relieving tightness and restoring movement and mobility throughout the entire body

Iconic style complemented with the signature comfort of the BIRKENSTOCK footbed

When every second counts in your long distance race

HSA/FSA approved

Drawcord Adjustment in back for perfect fit

2UNDR Swing Shift Boxer Brief Size:XXLarge ● Ideal for relieving tightnessThe Swing Shift caresses the skin with the finest beechwood fibre in our signature modal fabric. Additionally, the material resists shrinkage and is less likely to fade or pill. Perfection in your pants. The Swing Shift caresses the skin with the finest beechwood fibre in our signature Modal fabric. Pure heavenly softness. Perfection in your pants. Patented Joey Pouch for support and comfort No Drip Tip with hydrophobic membrane for a dry environment