pos/pos_cash_move_reason/wizard/pos_box.xml

<?xml version="1.0" encoding="UTF-8"?>
<openerp>
    <data>
        <record model="ir.ui.view" id="cash_box_in_form">
            <field name="name">cash.box.in.form</field>
            <field name="model">cash.box.in</field>
            <field name="inherit_id" ref="account.cash_box_in_form" />
            <field name="arch" type="xml">
                <xpath expr="//field[@name='name']" position="before">
                    <field name="product_id" required="1" class="oe_inline" />
                </xpath>
            </field>
        </record>

        <record model="ir.ui.view" id="cash_box_out_form">
            <field name="name">cash.box.out.form</field>
            <field name="model">cash.box.out</field>
            <field name="inherit_id" ref="account.cash_box_out_form" />
            <field name="arch" type="xml">
                <xpath expr="//field[@name='name']" position="before">
                    <field name="product_id" required="1" class="oe_inline"/>
                </xpath>
            </field>
        </record>
    </data>
</openerp>