gtag('event', 'purchase', { 'transaction_id': 't_12345', 'currency': 'USD', 'value': 1.23, user_data: { email_address: 'johnsmith@email.com', phone_number: '1234567890', address: { first_name: 'john', last_name: 'smith', city: 'menlopark', region: 'ca', postal_code: '94025', country: 'usa', }, }, items: [{ item_name: 'foo', quantity: 5, price: 123.45, item_category: 'bar', item_brand : 'baz', }], });