FLY London NWOB Stif Black Leather Women's Strap Front Boots EU 38 US 7/7.5. Fly London Stif boots, which are a military-style boot known for their distressed leather, buckle detailing, and lugged sole. Fly London Stif boots are typically constructed from distressed leather and feature adjustable buckle straps on the front, contrasting stitching, and a round toe. Elevate your style with these sleek black and burgundy men's boots. Perfect for any occasion, these boots offer both comfort and durability.