A standard flatbed is the most common and is 48 or 53 feet in length. Flatbeds are generally about 60 inches high, which means they can carry freight up to 8' 6" high and not have any problems with bridges or overhead wires. A standard flatbed can carry freight that is up to 8' 6" wide without requiring any special permits. Wider shipments can be moved on flatbed but are considered "over-width" and require special permits. Anything over 11'6" wide will also need an escort. An escort is a special car with flashing lights that escorts the flatbed from origin to desitination for safety. Generally, "over-width" shipments can only travel during daylight hours so keep in mind that your transit time may be effected when shipping an "over-width" shipment on a flatbed.
Freight is also allowed to overhang the back of the flatbed trailer up to 10% of the trailers length. So a 48 foot flatbed could over hang 4'9" over the back of the tailer. However, you cannot make an oversized load, so if you ship two pieces on the same flatbed trailer, you cannot have any overhang.
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