Although the STL 2.0 is slightly smaller than the STL 2.5, The 2.5 manages to maintain a lightweight construction and a thin profile. Strong. Thin. Light. The STL 2.5 is an evolution of the original, still light at 1.5 ounces yet strong enough for your daily tasks. A cut out in the blade offers an easy one-handed opening, and the ultra-thin blade is longer for added value. A lanyard hole ensures it will always be on hand and ready.