For night work in a Nevada highway work zone, what feature may be added to cones, drums, and barricades?

Rear reflectors are required equipment on bicycles ridden at night, not on the cones, drums, and barricades used to guide drivers through work zones. This answer generalizes from the everyday rule that reflectors mean night visibility instead of checking what the manual actually attaches to work-zone equipment.

The manual does not list speed-enforcement equipment among the items that may be added to cones, drums, and barricades in a work zone. This answer assumes that because work zones carry doubled speeding fines, radar displays must be built into the barricades to enforce them.

Emergency flares are what a stopped motorist uses to warn traffic around a disabled vehicle, not gear attached to work-zone cones or barricades. This answer pictures the flares packed in a roadside emergency kit, since flares are the classic image of warning traffic after dark.