Trail King Trailers for sale at General Equipment & Supplies, Inc. Offering Trail King Trailers, material dumps to shed material, trailers with Hydraulic Detachable Gooseneck and Mechanical Detachable Gooseneck, Steel Side Dumps, parts and service from our locations in Bismarck, Fargo, Minot and Williston, North Dakota. Click the Images below for more details on the Trail King Trailer models offered at General Equipment & Supplies. *Vendor territories vary by location*