The Heil Trailer double conical crude oil trailer is the most durable trailer in the oil patch. This DOT-407 trailer can handle anything the tough off-road environment can dish out. The versatile Heil Trailer external ring design can be built with capacities from 200 barrels on up. Unique axle configurations are available for heavy weight states and for export into Canada. These trailers are designed and built to last and we back them with the industry’s longest and most comprehensive warranty.