The Demko AD20.5 Knife is an innovative EDC, designed by Andrew Demko, that features his patented Shark-Lock. This AD20.5 has a 3.25 inch clip point blade made of D2 tool steel, .13 inches thick, with a 3 inch cutting edge, a Black DLC finish, jimped thumb rest for precise control, an oval hole and dual thumb studs for ambidextrous one hand opening. The textured gray Grivory handle, 4.50 inches closed, has a caged ball bearing pivot for smooth action, steel liners for strength, the patented Shark-Lock, a lanyard hole and a removable steel pocket clip mounted at the butt end (a pocket clip for left hand carry is included). This Demko AD20.5 Knife has an overall open length of 7.625 inches, and it weighs 3.55 ounces. Made in Taiwan.
From Demko Knives regarding the Shark-Lock: The Shark-Lock mechanism is situated on the spine of the knife and operated with a ramp-like 'fin.' Opening the blade makes the spring-driven lock arm move up and then into a notch in the tang, situating it beneath a lock pin. This range of movement is noteworthy. It's unique in that the locking mechanism moves forward and back while also moving up and down. This allows for a greater sized blade tang, making a better mechanical advantage in a specific area. And because the drive spring that moves the locking element up into the locked position is contained within the locking arm itself, it won't be subject to dirt and grime. The Shark-Lock™ is very comparable to most Tri-Ad locks for its size and weight.