Evolving in parallel to development in the U.S., backhoes were first produced in the UK in 1953 by JCB, but it was just a prototype. The world's first backhoe loader with factory warranty was introduced in the U.S. by J.I. Case in 1957. Their Model 320 was the world's first serial backhoe loader. Although based on a tractor, a backhoe loader was and is almost never called a "tractor" when both the loader and the backhoe are permanently attached. Backhoe loaders are also not generally used for towing and usually do not have a power take-off (PTO) as often this is used to drive the hydraulic pump operating the attachments. When the backhoe is permanently attached, the machine usually has a seat that can swivel to the rear to face the hoe controls. Removable backhoe attachments almost always have a separate seat on the attachment itself.