ASP NET CRUD Web API Post Customer

PostCustomer.cs

 [ResponseType(typeof(Customer))]
        public IHttpActionResult PostCustomer(Customer customer)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            db.Customers.Add(customer);
            db.SaveChanges();

            return CreatedAtRoute("DefaultApi", new { id = customer.CustId }, customer);
        }