The bottom of the body was squared off using edge loops and the resize tool.
It was then extruded down, the back of that extrusion was extruded out away from the body, the faces of that extrusion were extracted into its own object, then that object was rounded of with edge loops.
The empty gap of the last extrusion was then brought in in order to form a seem with the new object that was extracted. the top faces of that object were extruded then cut in order to make a perforated clasp.