A loading unit includes a shell assembly, a lock collar, and a release collar.The shellassembly has a coupling ring that defines a lock slot and a proximal openingconfigured toreceive a distal end portion of a surgical instrument. The lock collar isdisposed about thecoupling ring and has a radially extending lock that is configured to bereceived within thelock slot. The lock collar is transitionable between a locked configuration inwhich the lockis positioned within the lock slot and an unlocked configuration in which thelock is liftedfrom within the lock slot. The release collar is disposed about the couplingring proximal ofthe lock collar and is transitionable between an unactuated position and anactuated position.The release collar transitioning the lock collar to the unlocked configurationas the releasecollar is translated from the unactutated position towards the actuatedposition.
