The side panels are usually wider than the cabinet itself. This is to cover the carcass itself, the thickness of the front (door) plus a few mm to be able to adjust the panel to the wall/floor which often turns out to be uneven. Side panels can always be customized by cutting the sides facing the wall or floor. If you are customizing side panels yourself, please take for a count that often they have to be adapted to the uneven floor, the wall, and the carcass itself. It must be considered that it is not always worthwhile to order side panels in exact measurements without having to adapt on-site as well. Side panels should be mounted from the inside of the cabinet using mounting screws. Screws do not come with side panels, so we recommend using very common mounting screws that can be purchased in places like Screwfix or B&Q. It is important not to use too long screws to avoid screws passing through the side panels. Side panels are 12mm thick. If you have no experience in joinery work, we always recommend using professionals for the best possible result.