Field help (MINQTY1) 

Minimum quantity for the assignment of this price list line.
This field can be specified only if the price list code has been set up to limit the application of the price lists according to a minimum quantity of purchase units (depends on the setup of the price list code - if in the Price tab, the "Price/Qty" field is set to "Yes" or "Qty sections").

When the line of the quote, the order, the delivery or the invoice is expressed in a different unit, this line is only used if this price list accepts the conversion of units.
For a grouped price list, the minimum quantity is compared with the quantity total of the lines meeting the criteria and displaying the same unit as the price list (or accepting the conversion of units).