Zero Tolerance’s 0055 caught our eye because it features a “hidden” flipper tab called the SLT, an innovative design from custom knifemaker Gus T. Cecchini. Rather than a large tab protruding from the blade’s tang like a dorsal fin, the 0055’s SLT is more like a tiny rounded lever that sits almost unnoticed at the top of the handle. The knife flicks open once the SLT is pulled back completely, feeling much like a two-stage AR-15 trigger. Once the 3.75-inch S35VN stainless steel blade deploys, the tab disappears into the 3D-machined framelock handle. The 8.75-inch-long knife comes with a reversible titanium pocket clip for righties and lefties. Made in the USA.