This part of ISO 7785 specifies requirements and test methods for straight and geared angle handpieces for application to patients. It also contains specifications on manufacturer's instructions, marking and packag-ing. These handpieces are operated by electrical or air-driven motors. In addition to these specified re-quirements, there are several other aspects of the materials, construction and general design of hand-pieces which cannot be objectively specified or as-sessed. They are considered to be complied with if the series of objectively verifiable requirements are fulfilled.