A lowboy (low-loader in British English, low-bed in western Canada and South Africa or float in Australia and eastern Canada) is a semi-trailer with two drops in deck height: one right after the gooseneck and one right before the wheels.
It offers the ability to carry legal loads up to 12 ft (3.66 m) tall, which other trailers cannot.
The first lowboy trailer was invented in the 1920s; it featured a riveted gooseneck and solid rubber tires.
The first detachable gooseneck trailer, referred to as an RGN (Removable goose neck), was invented in 1958.
[1] The lowboy trailer comes in several types,[2] for a wide range of tasks.