This boot lace bundle includes two pairs of Ironlace's unbreakable, indestructible boot laces designed to withstand the most demanding environments. Both pairs feature Ironlace's durable, 100% advanced para-aramid fiber construction that is 10 times stronger than steel with an impressive 1500-pound breaking strength per pair. The laces have a 3.2mm diameter to fit most boots and are guaranteed for life against damage, abrasion, UV exposure and corrosion. One pair measures 45 inches long while the other pair is 54 inches, providing versatile sizing options. Both pairs are colored brown to match most boot styles. The waterproof, fire and heat resistant laces can withstand temperatures up to 630°F, making them ideal for firefighters, welders and other industrial applications. Once laced up, the stretch-free laces stay securely tied and comfortable whether hiking, working on a job site or in harsh weather conditions. With one shorter and one longer pair of Ironlace's unbreakable laces created from an extremely durable para-aramid fiber, this bundle provides reinforced boot security across various environments and activities.