a handle having a chamber for selectively receiving a pivotally attached blade, the blade having a tang and being pivotal within a first plane between a closed position wherein the blade is located within the chamber and an open position wherein the blade resides outside the chamber;

a locking member attached to the handle adjacent the chamber, the locking member having a first thickness and including a contact surface that is selectively engagable with a rear peripheral edge of the tang of the blade when the blade is in the open position, wherein the locking member is disposed immediately adjacent the blade when the blade is in the closed position;

wherein the contact surface is substantially planar and has a second thickness that is greater than the first thickness and lies within a second plane that is generally perpendicular to the first plane;

wherein the handle includes first and second inner plates disposed in spaced relation between a pair of outer plates, the handle supporting a pivot pin;

the tang being pivotally attached to the handle about the pivot pin;

wherein the first inner plate has a slot formed therein so as to define the locking member, wherein the contact surface defines a locking edge that is biased inwardly towards the blade and an extension projecting outwardly from the locking edge, wherein the extension lies in a second plane that is different from a plane containing the lock member;

wherein a recess is formed in the outer plate adjacent the first inner plate; and

the extension being constructed to prevent the locking edge from inadvertently slipping from its abutting relationship with the tang end of the blade to ensure that the blade is securely held open in the extended position.