Such distribution transformers were typically connected to 1,100 or 2,200 volts on the primary side for 110 volt service to customers and made of heavy cast iron enclosures. A porcelain "cutout" is seen on the upper crossarm on its far left. These had a matching porcelain plug with a piece of fuse wire that inserted into the cutout's underside. Although these devices were absolutely needed since they electrically protected individual transformers, they were also known among linemen for many decades as "widow-makers". If their was a fault within the transformer or its load, the lineman manually plugging in the circuit would likely incur at least some degree of injury upon electrifying the short-circuit. Later fuse cutouts had rounded handles on their "doors" that made re-energizing more safe, using a special hook-stick for reclosing.