Product Line，产品线，或产品系列，是指一群相关的产品，这类产品可能功能相似，销售给同一顾客群，经过相同的销售途径，或者在同一价格范围内。

Product Line Stretching，产品线延申/扩展，公司通常会将新产品添加到现有的产品线中。它可以帮助他们根据客户的需求更新产品，并在市场上保持竞争力。Product Line Stretching是指在现有产品范围内增加产品总数的决策。

产品线延申/扩展的类型：

1、产品线向下延申（Downward Product Line Stretching）

2、产品线向上延申（Upward Product Line Stretching）

3、产品线双向延申（Two-way Product Line Stretching）

参考双语例句:

More companies are learning the importance of destructive technologies—innovations that hold the potential to make a product line, or even an entire business segment, virtually outdated. 

越来越多的公司正在意识到变革性技术的重要性，它几乎能令一条产品线、甚至是整个业务部门都因过时而被淘汰。

Mori Seiki will continue to improve our product line-up and create machines which will satisfy the needs of our customers.

森精机制作所将继续改善我们的产品线和生产满足客户需求的机床。

The comprehensive programme focused upon the sharing of new technological skills and production techniques for leadfree glazes and fuel substitution, the promotion of new designs inspired by tradition and product line elements and the marketing of these products in the light of global health concerns and international norms.

该综合性计划的重点是分享无铅釉和燃料替代物的新工艺技能和生产技术，促进以传统生产线为依据的新设计，并根据全球卫生要求和国际标准经销这些产品。

Martin has taken part in developing the group-level growth strategy for a leading high-tech original design manufacturer (ODM); shaping the product line strategy and product development process for a Taiwanese PC ODM; formulating a strategy and pricing tactics for a producer of high-tech components; and leading the reengineering of a major computer ODM in Taiwan.

贺睦廷参与了一家知名高科技原始设计制造商(ODM)的集团发展战略的制定；为一家台湾个人电脑原始设计制造商(ODM)理顺产品线的战略和产品开发流程；为一家高科技零部件生产企业设计战略和定价策略；并领导一家台湾主要计算机原始设计制造商的企业再造。