- Modus Vivendi military brief, a sharp modern approach to a classic underwear design. Made of pure ribbed Cotton (95% ) and Elastane (5% ). Leather look pouch (made of Polyester Fillam Pelle 100% ) with matching leg and waistband trim and cotton cords ending in metal aglets for the best fit possible. With a clear reference to military style, luxury fabrics and a distinctive look, this black brief makes a strong statement and offers supreme comfort.