Is it permissible to subscribe to a service that provides a monthly box containing various types of makeup, undefined in advance, or does that fall under selling based on gharar (unspecified or uncertain transactions)?

If a customer pays an annual subscription to a company for a makeup box whose contents are unknown, and if the samples vary in value and quality, then this contract is considered gharar (definition) (excessive uncertainty) and gambling, and it is impermissible due to the Prophet's (peace be upon him) prohibition of gharar sales. However, if the quantity is known and the value and quality are identical or differ only slightly, then there is no harm in the transaction, because minor and tolerated gharar is an exception. It appears that the gharar in this case is of the excessive type that invalidates the contract.