Product platforms has been widely accepted in industry as a means to reach both high product variety while maintaining business efficiency. For suppliers of highly customised products, however, the development of a platform based upon pre-defined modules is a challenge. This is due to the large differences between the various systems their products are to be integrated into and the customer’s individual preferences. What is common for most platform descriptions is the high level of concretisation, such as predefined modules, they are built upon, but how can companies act when that is not possible? Are there other principles that can be used for the definition of a product platform? This paper presents a concept to incorporate other types of descriptions of different levels of concretisation into a product platform. Parts of the concept has been realised in a computer support tool and tested at a case company in order to improve their quotation process.