Tilt before turn window handles, also known as TBT window handles, are window handles designed to open a window by tilting it upwards first and then turning it. This type of window handle is specifically intended for use on windows made of PVC (polyvinylchloride), which is a type of plastic commonly used for windows.
TBT window handles are designed to open a window in a way that puts less stress on the window and therefore reduces the risk of damage. They are also easier to operate than traditional window handles because they don't have to be turned to open the window. Instead, you can open the window by tilting it upwards and then turning it.
TBT window handles are available in a variety of styles and finishes and can be used on interior or exterior windows. Some TBT window handles also have a locking function to secure the window.