diff --git a/back/methods/collection/addItem.js b/back/methods/collection/addItem.js
index 26eb9cc27..3b2a6921b 100644
--- a/back/methods/collection/addItem.js
+++ b/back/methods/collection/addItem.js
@@ -6,7 +6,7 @@ module.exports = Self => {
         accepts: [
             {
                 arg: 'code',
-                type: 'number',
+                type: 'string',
                 required: true
             },
             {
diff --git a/back/methods/collection/spec/addItem.spec.js b/back/methods/collection/spec/addItem.spec.js
index 58cc97610..199aae588 100644
--- a/back/methods/collection/spec/addItem.spec.js
+++ b/back/methods/collection/spec/addItem.spec.js
@@ -1,7 +1,7 @@
 const {models} = require('vn-loopback/server/server');
 const LoopBackContext = require('loopback-context');
 
-fdescribe('collection addItem()', () => {
+describe('collection addItem()', () => {
     const quantity = 3;
     const ticketFk = 24;
     const warehouseFk = 1;
diff --git a/loopback/locale/en.json b/loopback/locale/en.json
index 391034126..e3d08326e 100644
--- a/loopback/locale/en.json
+++ b/loopback/locale/en.json
@@ -205,5 +205,6 @@
 	"It was not able to remove the next expeditions:": "It was not able to remove the next expeditions: {{expeditions}}",
 	"Incorrect pin": "Incorrect pin.",
 	"This machine is already in use.": "This machine is already in use.",
-	"This pallet does not exist": "This pallet does not exist"
+	"This pallet does not exist": "This pallet does not exist",
+	"We do not have availability for the selected item": "We do not have availability for the selected item"
 }
\ No newline at end of file
diff --git a/loopback/locale/es.json b/loopback/locale/es.json
index b273f7506..45de30904 100644
--- a/loopback/locale/es.json
+++ b/loopback/locale/es.json
@@ -341,5 +341,6 @@
 	"No hay tickets para sacar": "No hay tickets para sacar",
 	"There is no zone for these parameters 999999": "There is no zone for these parameters 999999",
 	"This machine is already in use.": "Esta máquina ya está en uso.",
-	"This pallet does not exist": "Este palet no existe"
+	"This pallet does not exist": "Este palet no existe",
+	"We do not have availability for the selected item": "No tenemos disponible el item seleccionado",
 }
\ No newline at end of file
diff --git a/modules/item/back/methods/item-shelving/makeMulti.js b/modules/item/back/methods/item-shelving/makeMulti.js
index e4393e4de..7d1ee11a0 100644
--- a/modules/item/back/methods/item-shelving/makeMulti.js
+++ b/modules/item/back/methods/item-shelving/makeMulti.js
@@ -47,10 +47,10 @@ module.exports = Self => {
                     }, 0);
                     discardItems.push(item);
 
-                    let [result] = await Self.rawSql('SELECT vn.itemPacking(?, ?)', [item, warehouseFk]);
+                    const [result] = await Self.rawSql('SELECT vn.itemPacking(?, ?) itemPacking', [item, warehouseFk]);
                     let packing;
 
-                    if (result) packing = Object.values(result)[0];
+                    if (result) packing = result.itemPacking;
                     if (!packing) packing = 1;
 
                     quantity = quantity * packing;
diff --git a/modules/item/back/methods/item-shelving/specs/makeMulti.spec.js b/modules/item/back/methods/item-shelving/specs/makeMulti.spec.js
new file mode 100644
index 000000000..f64a815f2
--- /dev/null
+++ b/modules/item/back/methods/item-shelving/specs/makeMulti.spec.js
@@ -0,0 +1,54 @@
+const {models} = require('vn-loopback/server/server');
+
+describe('item makeMulti()', () => {
+    const warehouseFk = 1;
+
+    beforeAll(async() => {
+        ctx = {
+            accessToken: {userId: 9},
+            req: {
+                headers: {origin: 'http://localhost'},
+            }
+        };
+    });
+
+    it('should add two new records', async() => {
+        const shelvingFk = 'ZPP';
+        const items = [1, 1, 1, 2];
+        const tx = await models.ItemShelving.beginTransaction({});
+        const options = {transaction: tx};
+
+        try {
+            await models.ItemShelving.makeMulti(shelvingFk, items, warehouseFk, options);
+            const itemShelvings = await models.ItemShelving.find({where: {shelvingFk}}, options);
+
+            expect(itemShelvings.length).toEqual(2);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+
+    it('should update the visible items', async() => {
+        const shelvingFk = 'GVC';
+        const items = [2, 2];
+        const tx = await models.ItemShelving.beginTransaction({});
+        const options = {transaction: tx};
+        try {
+            const {visible: itemsBefore} = await models.ItemShelving.findOne({
+                where: {shelvingFk, itemFk: items[0]}
+            }, options);
+            await models.ItemShelving.makeMulti(shelvingFk, items, warehouseFk, options);
+            const {visible: itemsAfter} = await models.ItemShelving.findOne({
+                where: {shelvingFk, itemFk: items[0]}
+            }, options);
+
+            expect(itemsAfter).toEqual(itemsBefore + 2);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+});