Let's say I produce beers and I sell them in boxes of 24 bottles

Setting a packaging in the inverory tab  of the product  will not help very much on the sale order because you have manually to calculate the number of units

If I sell to package I've to enter 48 ; i Would prefer to enter 2 x 24, but if I define a product as a 24 units box, then I can only handles boxes and not units

Is there any other way to achieve that ?

PS: By the way I find out in the Odoo documentation the following

"In Odoo, packagings are used for indicative purposes on sale orders. They can be specified on the product form, in the inventory tab."