MontBlanc Mens Belt Bag. SKU: 129984. Color: British green. Montblanc Extreme 3.0 Sling Bag. Compact and versatile, this sling bag is crafted from embossed full-grain bovine leather with the signature Extreme 3.0 motif and black metal fittings. Designed for modern urban life, it features internal pockets and credit card slots to keep essentials organized and accessible. Dimensions: 6.7 2.4 11.6.