A system for securing a loading unit to an adapter includes a loading unit, an adapter, and a retention clip. The loading unit includes a shell having a proximal end portion having a radial surface that defines a radial groove. The adapter has a proximal end that is configured to selectively couple to a handle and a distal end that is received within the proximal end portion of the shell. The retention clip is disposed radially about the radial surface of the proximal end portion within the radial groove. The retention clip has a first and a second and a body therebetween. The first end of the body includes a lock that releasably secures the loading unit to the distal end of the adapter.