a handle defined by a first handle side wall and a second handle side wall, said handle having a front end and a back end, and said handle defining a blade-receiving space with an opening into the space through the front end;

a blade slidable in the handle between a retracted position in which the blade is received in the blade-receiving space and an open position in which said blade extends through said opening, said blade having a working portion and a tang portion with a first raised portion thereon, and when said blade is in the open position said tang portion remains substantially within the blade-receiving space;

a first liner between one side of the blade and the handle, the liner having a central slot with a closed front end and said first raised portion of said tang portion received in said central slot:

a first spring for moving the blade from the retracted position to the open position;

a second spring for moving the blade from the open position to the retracted position;

wherein when said blade is in the open position a frontal surface of said first raised portion of said tang portion abuts said closed end of said central slot, and including a first lock operable to lock the blade in the open position, said first lock defined by a first latch arm operable to engage the raised portion of said tang portion of said blade when in the open position and apply pressure thereto, and a second latch arm operable to engage the raised portion of said tang portion of said blade when in the open position and apply pressure thereto, said first and second latch arms together urging said frontal surface of said first raised portion against said closed end of said first central slot.