This parameter is used to define if the expiry date must be entered manually upon a stock receipt, for those products managed with expiry dates. In that case, the entry is carried out by confirmation/modification of three sections: reference date for the calculation, expiry lead time (that of the default product record) and expiry date calculated according to the product expiry management mode. With the "Displayed" or "Hidden" values, the date is calculated automatically without the operator having to intervene. In stock issues, the expiry date can never be entered, it can nevertheless be displayed for information purposes.