US Patent 9155537 Surgical fastener applying apparatus

A surgical fastener applying apparatus for applying fasteners to body tissue. The apparatus includes a cartridge receiving half-section defining an elongated channel member configured to releasably receive a stationary housing of a firing assembly. The stationary housing is dimensioned to releasably receive a single use loading unit therein, and includes a lockout structure that prevents insertion of the single use loading unit into the stationary housing after the stationary housing is mounted to the cartridge receiving half-section.