Omega Technologies OM86-5 OM86 Series Hollow Cutter is designed to cut away swagged or threaded collars from fasteners so the fastener pin can be easily removed. Omega Technologies OM86-5 OM86 Series Hollow Cutter is ideal for removing Hi-Shear® rivets. The rotating cutter is applied to the collar until a sufficient amount of collar material has been removed. The pin is then easily removed with a punch. A microstop cage is typically used to prevent the cutter teeth from contacting and damaging the work surface.