Gearing up for production? Start here.

Five critical documents to know when working with contract manufacturers 

Contract manufacturers are in the business of building products that entrepreneurs like you have designed. They bring your vision to life in precise detail. In preparing to work with these vital partners, there are several documents you need to have ready to go when you approach them, from your product’s key components to the instructions for making to other detailed considerations.

There are lots of things you can do to increase your chances of signing a deal with a contract manufacturer. But having these five documents prepared in advance is an important place to start.

Bill of Materials (BOM)

A BOM is like the list of ingredients in a recipe. It lists the components that form your product, how those components relate, and how long it takes to produce each component (lead time). A BOM also describes the necessary quantities of those components and a product hierarchy that goes from the individual parts to the finished produced. It may also include engineering aspects of the product, such as subassemblies.

BOMs are important because they show contract manufacturers specific product parts so that they can maintain product consistency and understand costs. The document also ensures parts and materials are traceable, which some federal agencies require.

Bill of Process (BOP)

While a BOM is like the list of ingredients in your recipe, the BOP is like the recipe’s instructions. It describes the processes and sequence of production for your product, as well as the specifications and parameters of each step. BOPs are important because they ensure that the right resources are available when production begins—and that the product is built the same way every time. They also support regulatory and certification requirements.

A BOP usually takes the form of a table that includes routing information. BOPs typically number these processes—or operations—and describe each one in detail. They also outline the resources necessary for each operation. Operations include setup required for process; setup and cycle times; labor involved; necessary equipment, like tooling; and standard operating procedures (SOPs).

Engineering & Assembly Drawings Summary

A summary of your engineering and assembly drawings provides a visual representation of your product and components, including fit, tolerances, and assembly specifications.

Quality Manual

This document standardizes your approach to production—something every contract manufacturer will need to do their work for you. A Quality Manual features descriptions of rules and procedures necessary to make high-quality products to your specifications. Your contract manufacturer will use it to devise new processes or improve existing ones to maximize their efficiency while preserve high quality. They may use it to troubleshoot production issues, too. The key sections of a Quality Manual are:

  • Your mission statement, to set expectations.

  • Your company values, to help contract manufacturers make decisions about quality and safety.

  • Instructions about how to perform tasks like inspection, calibration, and maintenance schedules.

  • Your company policies related to health, safety, environment protection.

Product Requirements Document (PRD)

This document has a particularly vital role in ensuring product quality and controlling production costs, because it answers key questions across an array of subjects, from a product description to regulatory and financial considerations, to design and packaging.

  • Product—Explains why the marketplace needs this product, what it does, and the features that will make it valuable and successful for customers.

  • People—Describes the end users of your product, and what they care about, as well as those who will be involved in selling, shipping, installing, and repairing the product.

  • Regulatory—Explains any legal considerations necessary for your product to be sold.

  • Financial—Describes anticipated pricing for customers, as well as costs to build and ship.

  • Industrial Design—Focusing on the usability and aesthetics of your product, in terms of the way users will interact with it.

  • Packaging—Covers how your product will be contained for safe shipping, and what information needs to be included.

  • Serviceability—Policies related to service and repair of your product.


These five standard documents are necessary when you’re looking to do business with a contract manufacturer because they communicate technical instructions and requirements. And Scale for ClimateTech has plenty of resources to help you get started in preparing them, including this helpful tool.