diff --git a/kfet/templates/kfet/kpsul.html b/kfet/templates/kfet/kpsul.html
index 47feb71b..4be8b48e 100644
--- a/kfet/templates/kfet/kpsul.html
+++ b/kfet/templates/kfet/kpsul.html
@@ -886,6 +886,26 @@ $(document).ready(function() {
         updateBasketRel();
     }
 
+    function addExistingPurchase(opeindex, nb) {
+        type = formset_container.find("#id_form-"+opeindex+"-type").val(); 
+        id = formset_container.find("#id_form-"+opeindex+"-article").val(); 
+        nb_before = parseInt(formset_container.find("#id_form-"+opeindex+"-article_nb").val()); 
+        nb_after = nb_before + nb;
+        if (type == 'purchase') {
+            if (nb_after == 0) {
+                deleteFromBasket(opeindex);
+            } else if (nb_after > 0 && nb_after <= 25) {
+                amountEuro_after = amountEuroPurchase(id, nb_after);
+                amountUKF_after = amountToUKF(amountEuro_after, account_data['is_cof']);
+                basket_container.find('[data-opeindex='+opeindex+']')
+                                .find('.amount').text(amountUKF_after).end()
+                                .find('.number').text(nb_after).end() ;
+                updateExistingFormset(opeindex, nb_after, amountEuro_after);
+                updateBasketRel();
+            }
+        }
+    }
+
     function resetBasket() {
         basket_container.find('tr').remove();
         mngmt_total_forms = 1;
@@ -1022,6 +1042,12 @@ $(document).ready(function() {
         formset_container.find('#id_form-'+opeindex+'-DELETE').prop('checked', true);
     }
 
+    function updateExistingFormset(opeindex, nb, amount) {
+        formset_container
+            .find('#id_form-'+opeindex+'-amount').val((parseFloat(amount)).toFixed(2)).end()
+            .find('#id_form-'+opeindex+'-article_nb').val(nb);
+    }
+
     // -----
     // History
     // -----