question

The original item enters the combiner by the input port number 1. You pull the secondly divided item through the input port 2 by the Requirement that the label value of the first item in the combiner matches with the label value of the currently tested item. If there a match, the tested item will enter the combiner.

Object itemToMatch = NULL; 
/**Port 1 anything, Port 2 matching label "Id" value*/
if (port == 1) return 1;
if (port > 1){
   itemToMatch = current.first;
   return itemToMatch.Id == item.Id; 
// logical comparison match = TRUE (1) or FALSE (0)
}

All items your are testing must have got the label you test. The label value must be different for non splitted items for example -100.

You assign an "Id" label value by connecting the output of an object.

Label value:

getoutput(current)+1

since FlexSim Version 18

current.stats.output.value+1

If you want that the combined items are stacked and the still look like a box, then you open the Flowitem Bin and copy a Pallet. You copy the path of the Box Flowitem for the shape to the copied Flowitem.

fs3d\General\Box.3ds

You adjust the size [0.61, 0.61, 0.30] of the copied pallet. And you pick by the sampler tool the color of the Box Flowitem from an item in your model that has ran before and has been stopped.

You set this new Flowitem Type to be created in your source.

combine-items-by-matching-id.fsm