CONCEPT 400ELACASSEA Universal Solution If you like to have a choice, then Concept 400E is the one for you. This line gives you an ageless design with an abundance of forms, components and finishes. It is also a perfect selection of furniture for your reception area and your conference room. Concept 400E is more than 300 components you can play with. It is a wide array of solutions for your workspace and storage needs. Concept 400E offers infinite solutions!