The expansion of these models becomes a greater reality each and every day. All-electric semi truck achieves first-of-its-kind feat: 'Progress is 100% being made' first appeared on The Cool Down.

Have you noticed those bars that hang from the bottom of the rear of semi-trucks? They’re called underride guards, and they have an important safety purpose.

The semi trucks were parked outside the El Paisano Warehouse, near 38th Street and Interstate 465. A still from INDOT camera ...