we would properly tutorial the purchasers about the application techniques to adopt our items plus the way to select appropriate materials. for interactive touch board for teaching Best Source has set up a strong sales and after-sales team to provide the best product and service. Best Source abides by the idea of "Grow with customer" and philosophy of "Customer-oriented" to achieve cooperation of mutual trust and benefit. Best Source will always stand ready to cooperate with you. Let's grow together!