This Japanese Industrial Standard specifies the characteristic of steel slotted head machine screws (hereinafter referred to as the "steel machine screws"), brass slotted head machine screws (hereinafter referred to as the "brass machine screws") and stainless steel slotted head machine screws (hereinafter referred to as the "stainless steel machine screws") to be used for the precision instruments such as optical instru¬ments and measuring instruments.
In this Standard, steel machine screws, brass machine screws and stainless steel machine screws are named generically "machine screws".