A surgical fastener applying apparatus for applying fasteners to body tissue. The apparatus includes a clamping lever including a cantilevered locking member for engaging a catch member positioned at the proximal portion of a cartridge receiving half-section of the apparatus to retain the clamping lever in a clamped position. The clamping lever can include a protrusion which is receivable in a depression on the cartridge receiving half-section. The apparatus includes a disposable firing assembly and cartridge.