Cutters of this form factor were the earliest milling cutters developed. Hard rock TBMs excavate rock with disc cutters mounted in the cutter head. Mats can be cut using computerized mat cutters. A special grinding profile that is used to grind milling cutters and twist drills. Other machines used include mowers, reapers, binders, harvesters, pea cutters and flax pullers. They remove material at a rate typically eight times faster than cemented carbide cutters. There are two types of pipe cutters. They worked such jobs as coiners, melters, pressers, cutters, and rollers. A specialized use of CNC Plasma Cutters has been in the HVAC industry. The padlock on the gate was cut with a pair of bolt cutters. These specialty cutters tend to be expensive. These new bits became known as router bits or router cutters (UK). The use of iron cutters and plows was also favoured among the farmers. Some dedicated models double as synthetic rope cutters. Pressurized water is used in water blasting and water jet cutters.