You fill out this field when the product has a physical location and a serial number. In this case, the product amount must be equal to 1 (1 piece) because the serial number is controlled for each product.

It is also used in the Field Service (Technical Assistance) module to control the product in an installed base, as long as the field Tech. Upd. (F4_ATUTEC), of the TIO register, is configured according to the situation.