manufacture right qty and traceable menthod

Accept/Reject containers at point of manufacture. If you cannot count the parts weigh them at finish. Record accept, reject, material input and scrap weights and then do the simple math subtractions to get your costs. You can do this electronically or the old way with a pencil/pen.

reject is zero, however, delivery by qty pcs, but material thickness variation 0.040-0.002"/+0.003" , min at max weight per pc difference is more than 10%. math could not use here for pieces qty.

thinking of anywhere exist a simple sensor with counter...a ticker will accumulate a qty "1", since it is dedecate machine, ytd pieces will show on sensor display counter . any one know this anywhere exists? thanks