Ruling on the Agreement to Manufacture Goods and Defer the Price

Now, some merchants buy goods from a factory owner, and they agree on them according to a model. Is this sale considered a salam sale?And if the merchant says: I cannot pay the full amount, but rather I pay it in installments so that I can secure my right?
This is not a salam sale; this is called the manufacture of goods. It is permissible to agree with the owner of a factory, whether a carpenter, a blacksmith, or others, on a specific item described and defined by its characteristics, and he does not deliver it until it is completed, whether the price is paid in full or in part.