diff --git a/account.py b/account.py
index 6a56971..1e047df 100644
--- a/account.py
+++ b/account.py
@@ -4,6 +4,7 @@ from trytond.model import fields
 from trytond.pool import PoolMeta
 from trytond.pyson import Eval
 from trytond.transaction import Transaction
+from trytond.tools import cached_property
 from .aeat import (BOOK_KEY, OPERATION_KEY, SEND_SPECIAL_REGIME_KEY,
     RECEIVE_SPECIAL_REGIME_KEY, IVA_SUBJECTED, EXEMPTION_CAUSE,
     IVA_NOT_SUBJECTED)
@@ -114,6 +115,17 @@ class Tax(metaclass=PoolMeta):
     sii_exemption_cause = fields.Selection(EXEMPTION_CAUSE, 'Exemption Cause')
     tax_used = fields.Boolean('Used in Tax')
     invoice_used = fields.Boolean('Used in invoice Total')
+    recargo_equivalencia = fields.Boolean('Recargo Equivalencia',
+        help='Indicates if the tax is Recargo de Equivalencia')
+    recargo_equivalencia_related_tax = fields.Many2One(
+        'account.tax', 'Recargo Equivalencia Related Tax',
+        domain=[
+            ('recargo_equivalencia', '=', True),
+            ('company', '=', Eval('company', -1)),
+            ], depends=['recargo_equivalencia', 'company'],
+        help='The possible Recargo Equivalencia related to this tax')
+    deducible = fields.Boolean('Deducible',
+        help='Indicates if the tax is deductible')
 
     @classmethod
     def __register__(cls, module_name):
@@ -134,3 +146,7 @@ class Tax(metaclass=PoolMeta):
 
         if exist_sii_intracomunity_key:
             table.drop_column('sii_intracomunity_key')
+
+    @staticmethod
+    def default_deducible():
+        return True
diff --git a/sii_core.xml b/sii_core.xml
index 05eadb3..71d1337 100644
--- a/sii_core.xml
+++ b/sii_core.xml
@@ -2,7 +2,15 @@
 <!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
 this repository contains the full copyright notices and license terms. -->
 <tryton>
-    <data depends="account_es">
+    <data>
+        <!-- Tax view-->
+        <record model="ir.ui.view" id="tax_form_view">
+            <field name="model">account.tax</field>
+            <field name="inherit" ref="account.tax_view_form"/>
+            <field name="name">tax_form_core</field>
+        </record>
+
+        <!-- Taxes -->
         <record model="account.tax.template" id="account_es.iva_sop_21_normal">
             <field name="sii_book_key">R</field>
             <field name="sii_received_key">01</field>
@@ -121,15 +129,16 @@ this repository contains the full copyright notices and license terms. -->
         <record model="account.tax.template" id="account_es.iva_sop_intracomunitario_servicios_1_normal">
             <field name="sii_book_key">R</field>
             <field name="sii_received_key">09</field>
-            <field name="sii_exemption_cause">E6</field>
-            <field name="tax_used" eval="False"/>
+            <field name="sii_subjected_key">S1</field>
+            <field name="sii_exemption_cause"></field>
+            <field name="tax_used" eval="True"/>
             <field name="invoice_used" eval="True"/>
         </record>
         <record model="account.tax.template" id="account_es.iva_sop_intracomunitario_servicios_2_normal">
             <field name="sii_book_key">R</field>
             <field name="sii_received_key">09</field>
             <field name="sii_subjected_key">S1</field>
-            <field name="tax_used" eval="True"/>
+            <field name="tax_used" eval="False"/>
             <field name="invoice_used" eval="True"/>
         </record>
         <record model="account.tax.template" id="account_es.iva_sop_intracomunitario_inv_1_normal">
diff --git a/view/tax_form_core.xml b/view/tax_form_core.xml
new file mode 100644
index 0000000..2a49a85
--- /dev/null
+++ b/view/tax_form_core.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0"?>
+<!--The COPYRIGHT file at the top level of this repository
+contains the full copyright notices and license terms. -->
+<data>
+    <xpath expr="/form/notebook/page[@id='general']/field[@name='update_unit_price']"
+        position="after">
+        <label name="deducible"/>
+        <field name="deducible"/>
+        <label name="recargo_equivalencia"/>
+        <field name="recargo_equivalencia"/>
+        <label name="recargo_equivalencia_related_tax"/>
+        <field name="recargo_equivalencia_related_tax"/>
+    </xpath>
+</data>