Magnetic Based Drills are simply stated a 'Portable Machine Shop'. Machines weighing a little as 21# are drilling holes in excess of 1" diameter while drills weighing up to 61# are drilling 3-1/16" through 3" mild steel. This is a real contrast to the mega monsters of the past weighing 70# drilling 5/8" and 3/4" holes.
Drills today use cutters of Hi-Speed Steel and Carbide to match the application. Each type of tooling has its merit and specific application. A careful review of the pages to follow will help you match the machine to your hole requirement.