diff --git a/db/routines/vn/procedures/itemShelving_add.sql b/db/routines/vn/procedures/itemShelving_add.sql
index 02762fa0b..2a4676b50 100644
--- a/db/routines/vn/procedures/itemShelving_add.sql
+++ b/db/routines/vn/procedures/itemShelving_add.sql
@@ -19,6 +19,10 @@ BEGIN
 	DECLARE vItemFk INT;
 
 	SELECT barcodeToItem(vBarcode) INTO vItemFk;
+	
+	SET vPacking = COALESCE(vPacking, GREATEST(vn.itemPacking(vBarcode,vWarehouseFk), 1));
+
+	SET vQuantity = vQuantity * vPacking;
 
 	IF (SELECT COUNT(*) FROM shelving WHERE code = vShelvingFk COLLATE utf8_unicode_ci) = 0 THEN
 
diff --git a/modules/item/back/methods/item-shelving/specs/addListByItem.spec.js b/modules/item/back/methods/item-shelving/specs/addListByItem.spec.js
new file mode 100644
index 000000000..e31ff2e61
--- /dev/null
+++ b/modules/item/back/methods/item-shelving/specs/addListByItem.spec.js
@@ -0,0 +1,55 @@
+const {models} = require('vn-loopback/server/server');
+const LoopBackContext = require('loopback-context');
+
+describe('ItemShelving upsertItem()', () => {
+    const warehouseFk = 1;
+    let ctx;
+    let options;
+    let tx;
+
+    beforeEach(async() => {
+        ctx = {
+            req: {
+                accessToken: {userId: 9},
+                headers: {origin: 'http://localhost'}
+            },
+            args: {}
+        };
+
+        spyOn(LoopBackContext, 'getCurrentContext').and.returnValue({
+            active: ctx.req
+        });
+
+        options = {transaction: tx};
+        tx = await models.ItemShelving.beginTransaction({});
+        options.transaction = tx;
+    });
+
+    afterEach(async() => {
+        await tx.rollback();
+    });
+
+    it('should add two new records', async() => {
+        const shelvingFk = 'ZPP';
+        const items = [1, 1, 1, 2];
+
+        await models.ItemShelving.upsertItem(ctx, shelvingFk, items, warehouseFk, options);
+        const itemShelvings = await models.ItemShelving.find({where: {shelvingFk}}, options);
+
+        expect(itemShelvings.length).toEqual(2);
+    });
+
+    it('should update the visible items', async() => {
+        const shelvingFk = 'GVC';
+        const items = [2, 2];
+        const {visible: itemsBefore} = await models.ItemShelving.findOne({
+            where: {shelvingFk, itemFk: items[0]}
+        }, options);
+        await models.ItemShelving.upsertItem(ctx, shelvingFk, items, warehouseFk, options);
+        const {visible: itemsAfter} = await models.ItemShelving.findOne({
+            where: {shelvingFk, itemFk: items[0]}
+        }, options);
+
+        expect(itemsAfter).toEqual(itemsBefore + 2);
+    });
+});
diff --git a/modules/item/back/methods/item-shelving/upsertItem.js b/modules/item/back/methods/item-shelving/upsertItem.js
new file mode 100644
index 000000000..49c2f1b0d
--- /dev/null
+++ b/modules/item/back/methods/item-shelving/upsertItem.js
@@ -0,0 +1,64 @@
+module.exports = Self => {
+    Self.remoteMethodCtx('upsertItem', {
+        description: 'Add a record or update it if it already exists.',
+        accessType: 'WRITE',
+        accepts: [{
+            arg: 'shelvingFk',
+            type: 'string',
+            required: true,
+        },
+        {
+            arg: 'items',
+            type: ['number'],
+            required: true,
+            description: 'array of item foreign keys'
+        },
+        {
+            arg: 'warehouseFk',
+            type: 'number',
+            required: true
+        }],
+
+        http: {
+            path: `/upsertItem`,
+            verb: 'POST'
+        }
+    });
+
+    Self.upsertItem = async(ctx, shelvingFk, items, warehouseFk, options) => {
+        const myOptions = {userId: ctx.req.accessToken.userId};
+        let tx;
+
+        if (typeof options == 'object')
+            Object.assign(myOptions, options);
+
+        if (!myOptions.transaction) {
+            tx = await Self.beginTransaction({});
+            myOptions.transaction = tx;
+        }
+
+        const discardItems = new Set();
+        const itemCounts = items.reduce((acc, item) => {
+            acc[item] = (acc[item] || 0) + 1;
+            return acc;
+        }, {});
+
+        try {
+            for (let item of items) {
+                if (!discardItems.has(item)) {
+                    let quantity = itemCounts[item];
+                    discardItems.add(item);
+
+                    await Self.rawSql('CALL vn.itemShelving_add(?, ?, ?, NULL, NULL, NULL, ?)',
+                        [shelvingFk, item, quantity, warehouseFk], myOptions
+                    );
+                }
+            }
+
+            if (tx) await tx.commit();
+        } catch (e) {
+            if (tx) await tx.rollback();
+            throw e;
+        }
+    };
+};
diff --git a/modules/item/back/models/item-shelving.js b/modules/item/back/models/item-shelving.js
index 98ff18931..c031d8271 100644
--- a/modules/item/back/models/item-shelving.js
+++ b/modules/item/back/models/item-shelving.js
@@ -1,4 +1,5 @@
 module.exports = Self => {
     require('../methods/item-shelving/deleteItemShelvings')(Self);
+    require('../methods/item-shelving/upsertItem')(Self);
     require('../methods/item-shelving/getInventory')(Self);
 };