Specification (technical standard)

https://en.wikipedia.org/wiki/Specification_(technical_standard)

A requirement specification is a set of documented requirements to be satisfied by a material, design, product, or service.[1]

A functional specification is closely related to the requirement specification and may show functional block diagrams.

A design or product specification describes the features of the solutions for the Requirement Specification, referring to the designed solution or final produced solution. Sometimes the term specification is here used in connection with a data sheet (or spec sheet). This may be confusing. A data sheet describes the technical characteristics of an item or product as designed and/or produced. It can be published by a manufacturer to help people choose products or to help use the products. A data sheet is not a technical specification as described in this article.

A Guide to Writing Specifications

http://notebook.lausd.net/pls/ptl/docs/PAGE/CA_LAUSD/FLDR_ORGANIZATIONS/FLDR_BUSINESS_SVCS/GUIDE%20TO%20WRITING%20SPECS.DOC.PDF

Types of Specifications

http://drsmau.in/typeofspecifications.php

Qualified products list

http://itlaw.wikia.com/wiki/Qualified_products_list

a list of products that have met the qualification requirements stated in the applicable specification, including appropriate product identification and test or qualification reference number, with the name and plant address of the manufacturer and distributor, as applicable

A qualified products list identifies various brands that have met specific criteria.

Design specification

https://en.wikipedia.org/wiki/Design_specification

Design specifications detail the characteristics that an item must possess to meet your specific requirements. 

They state what materials or methods must be used, or tell the contractor how to go about doing the work.

Performance Specifications 

Performance specifications say what the product must do or what end result will be produced. 

Performance specifications describe the performance requirements that a product has to meet.

Item Specifications 

You should be very careful about specifying equipment by make and model number. This practice is not considered proper in public contracts since it is

unfair to competing contractors.

Freight and Delivery Specifications

It is common practice for a manufacturer to coordinate the shipping arrangements. 

Installation Requirements

Warranties

Extended Warranties

Statements of Work/Services