bowls, conveyor systems, rollers, and chutes. PTFE can also be reinforced where abrasion is present – for equipment processing seeded or grainy dough for example. PTFE has been experimented with for electroless nickel plating. PTFE tubing is used for Bowden tubing in 3D printers because its low friction allows the extruder stepper motor to push filament through it more easily. PTFE is commonly used in aftermarket add-on mouse feet for gaming mice to reduce friction of the mouse against the mouse pad, resulting in a smoother glide. PTFE foils are commonly used with laserprinters everywhere, in their fuser unit, wrapped around the heater element(s) and as well on the opposite pressure roller to prevent any kind of sticking to it (neither the printed paper nor toner waste) PTFE is also used to make body jewellery as it's much safer to wear compared to materials like acrylic, that release toxics into the body at 26.6°C, unlike PTFE at 650–700°C. PTFE is used to make bookbinding tools for folding, scoring and separating sheets of paper. These are typically referred to as Teflon bone folders. Safety While PTFE is stable and nontoxic at lower temperatures, it begins to deteriorate at temperatures of about , it decomposes above , and pyrolysis occurs at temperatures above . The main decomposition products are fluorocarbon gases and a sublimate, including tetrafluoroethylene (TFE) and difluorocarbene radicals (RCF2). An animal study conducted in 1955 concluded that it is unlikely that these products would be generated in amounts significant to health at temperatures below . Above those temperatures the degradation by-products can be lethal to birds, and can cause flu-like symptoms in humans (polymer fume fever), although in humans those symptoms disappear within a day or two of being moved to fresh air. Most cases of polymer fume fever in humans occur due to smoking PTFE-contaminated tobacco, although cases have occurred in people who have welded near PTFE components or heated PTFE-coated cookware at for at least 4 hours. Teflon-coated cookware is unlikely to reach dangerous temperatures with normal use, as meat is usually fried between , and most cooking oils (except refined safflower and avocado oils) start to smoke before a temperature of is reached. A 1973 study by DuPont's Haskell Laboratory found that a 4-hour exposure to the fumes emitted by teflon cookware heated to was lethal for parakeets, although that was a higher temperature than the required