Sometimes you want to sell some items packaged together instead of separately. Such a package is usually called a kit in your Point of Sale software, or a Bill Of Materials if the package is the result of a manufacturing process.
Normally, kits appear in your software just as any other item, and can have a price independently of the sales price of the individual component. Of course the software calculates the costs of the kit based on the sum of the costs of the components. In the properties of the kit, you can specify which items are part of the kit, and how many units of each item are included. Sometimes you can even include kits as a component of another kit. The latter comes in handy in food processing, where for example you pre-prepare the pizza foundation using flour, yeast, milk,… and after that use the foundation as one of the components of the final pizza. You might also see such layered kits in the computer shop, that bundles a printer with the corresponding printer cable, and might want to offer a complete set containing a PC, monitor and printer (including the cable) for a special price.
A handy trick is to add the time needed to physically create the kit as one of the components of the kit, so the costs of the kit reflect the real costs. The software usually allows for modifications in the bill of materials when finishing the work order to reflect breakage and variations. If you fill in the actual time needed to create the kit, the POS system will calculate very precise margins on each sale!