These tend to be the most cost-effective way to exhibit at an exhibition or trade show. You book a certain size shell scheme package through the event organiser and are provided with the walls and usually a standard power socket. For these type of stands you have a few options:

Bring your own portable exhibition materials such as roller banners, pop-ups and fabric frames and sit them within your shell space

Dress the walls of the shell scheme itself with infill graphics or a shell cladding system

Upgrade the structure of the shell through the event organiser to include counters and storage rooms amongst other things

Contract a trusted professional team to build a stand for you within the shell scheme to cover the walls and give you additional functionality like storage cupboards, AV screens, lighting and counters