diff --git a/addons/mail/static/src/js/mail.js b/addons/mail/static/src/js/mail.js
index 9aed41c0708..e93a762981b 100644
--- a/addons/mail/static/src/js/mail.js
+++ b/addons/mail/static/src/js/mail.js
@@ -56,12 +56,14 @@ openerp.mail = function (session) {
 
         /* Get an image in /web/binary/image?... */
         get_image: function (session, model, field, id, resize) {
-            return session.prefix + '/web/binary/image?session_id=' + session.session_id + '&model=' + model + '&field=' + field + '&id=' + (id || '') + '&resize=' + (resize ? encodeURIComponent(resize) : '');
+            var r = resize ? encodeURIComponent(resize) : '';
+            id = id || '';
+            return session.url('/web/binary/image', {model: model, field: field, id: id, resize: r});
         },
 
         /* Get the url of an attachment {'id': id} */
         get_attachment_url: function (session, attachment) {
-            return session.origin + '/web/binary/saveas?session_id=' + session.session_id + '&model=ir.attachment&field=datas&filename_field=datas_fname&id=' + attachment['id'];
+            return session.url('/web/binary/saveas', {model: 'ir.attachment', field: 'datas', filename_field: 'datas_fname', id: attachment['id']});
         },
 
         /**
diff --git a/addons/point_of_sale/static/src/js/models.js b/addons/point_of_sale/static/src/js/models.js
index 7301a85eb2d..f1462424f1e 100644
--- a/addons/point_of_sale/static/src/js/models.js
+++ b/addons/point_of_sale/static/src/js/models.js
@@ -320,7 +320,7 @@ function openerp_pos_models(instance, module){ //module is instance.point_of_sal
 
     module.Product = Backbone.Model.extend({
         get_image_url: function(){
-            return '/web/binary/image?session_id='+instance.session.session_id+'&model=product.product&field=image&id='+this.get('id');
+            return instance.session.url('/web/binary/image', {model: 'product.product', field: 'image', id: this.get('id')});
         },
     });
 
diff --git a/addons/point_of_sale/static/src/js/widgets.js b/addons/point_of_sale/static/src/js/widgets.js
index c7874a4bd5c..4728c584b21 100644
--- a/addons/point_of_sale/static/src/js/widgets.js
+++ b/addons/point_of_sale/static/src/js/widgets.js
@@ -474,7 +474,7 @@ function openerp_pos_widgets(instance, module){ //module is instance.point_of_sa
         },
 
         get_image_url: function(category){
-            return '/web/binary/image?session_id='+instance.session.session_id+'&model=pos.category&field=image&id='+category.id;
+            return instance.session.url('/web/binary/image', {model: 'pos.category', field: 'image', id: category.id});
         },
 
         renderElement: function(){