Fellings’ Horizontal Directional Drill Trailers are used to transport directional boring machines known as horizontal directional drills (HDD), used for horizontal underground drilling/directional boring. HDD is a minimal-impact trenchless method of installing underground utilities such as pipes, conduits, or cables. Felling offers two classes of HDD trailers: Drop Deck I Drill Series, deck between the wheels, models with 12K-27K capacities, and Low Pro Drill Series, deck-over flatbed tag trailers with 30K-50K capacities.