覆盖具有1 mm及以下模块的齿轮，包括第一和第二首选项。两个基本齿条（一个带有齿隙余量）；修改齿顶和中心距以适应各种条件。四级精度，基本和双面复合测试公差。附录给出了单侧面试验、测量销尺寸计算以及各种设计条件下的计算示例。公制等同于英国标准978-1。交叉引用:BS 308BS 978:第1BS 978部分:第2BS 2519BS 4500部分

Covers gears having modules of 1 mm and less including first and second preferences. Two basic racks (one with backlash allowance); modification of addendum and centre distance to suit various conditions. Four grades of accuracy with elemental and dual flank composite test tolerances. Appendices give information on single flank testing, calculation of measuring pin dimensions and examples of calculations for various design conditions. Metric equivalent of BS 978-1.Cross References:BS 308BS 978:Part 1BS 978:Part 2BS 2519BS 4500