In designing the DAF M39, Van Doorne deliberately strived for modernity. A traditional construction based on some pre-existing truck chassis was unacceptable for that reason alone. A brandnew design however, also had the advantage of being able to apply the most weight-efficient configuration. Partly this was achieved by a welded monocoque design that needed no heavy chassis girders, but also by the use of sloped armour, that could approach the ideal envelopment of a given inner space. This was most apparent with the "Pantrado 2" design that used many facets to approximate the desired curvature. This would have worked even better through the use of cast armour, but casting would have been too expensive. In fact that was even true for the complex form of the Pantrado 2; the Pantrado 3 therefore showed a simplified hull shape, reducing the number of welds; a comparison has been made with the T-34 design. In cross-section the hull was essentially a hexagon and the intersection formed by the truncating glacis, or sloped frontal plate, was therefore hexagonal too. This was somewhat obscured by the fact that this glacis gradually merged with the front fenders. The front glacis connected to the bottom plate via a narrow strongly curved section. The back plate too was hexagonal but more reclined; it was at its underside joined to a lower back glacis plate, both forming a wedge. The upper and lower side plates also formed wedges.