A surgical fastener applying apparatus for applying fasteners to body tissue.Theapparatus includes a cartridge receiving half-section defining an elongatedchannel member, ananvil half-section, and a clamping lever. The cartridge receiving half-sectionreleasably receivesa cartridge and a firing assembly. The clamping lever includes a protrusion ina sidewall whichis receivable in a bifurcated depression formed in a sidewall of the cartridgereceiving half--sectionto releasably retain the clamping lever in a non-clamped position and in aclampedposition. The apparatus includes a disposable firing assembly and SULU.