Abstract: A folding knife is provided which has a blade, a main handle and a tail handle. The tail handle is pivotably engaged to the main handle. When the knife is in a work configuration, a free end of the tail handle is swung to engage a blade end of the main handle and, together with the main handle, the tail handle forms a grip from which the blade extends. Both the main handle and the tail handle have grooves, such that when the tail handle is swung away from the main handle into an open position, the handles together form a sheath for the blade. With the main handle and the tail handle so configured, the blade of the folding knife can be longer than the grip and yet still be sheathed when the blade is swung into the sheath formed by the main handle and the tail handle for storage. The knife preferably has a tip encasing assembly attached to the tail handle which prevents the blade from being accidentally disengaged from the sheath.

Abstract: A tri-fold knife is provided which has a blade having a tang and bifurcated handle. The handle has a main handle which has a forward end which is pivotably attached to the tang. The main handle terminates in a butt end. A tail handle is provided with a forward engaging end and a butt end coupling which pivotably engages the butt end of the main handle. The main handle is provided with a main handle slot and the tail handle is provided with a tail handle slot which connects with the main handle slot. When the main handle forward end engages the tail handle forward engaging end, a knife handle is formed. When the tail handle is end to end with the main handle, the slots form a sheath into which the knife blade can be pivoted. Preferably, locks are provided to hold the blade with respect to the main handle when the knife is opened and the blade is exposed. A lock is also provided to hold the blade in the closed position where the blade lies in the main handle slot and the tail handle slot.