We have known Lemon for over 10 years and we have been using the pipe expander supplied by HEI YAN GROUP. We have purchased 4 machines successively. When we first went into production, the machine didn't run well, and Lemon and his engineers took great care to debug the machine and coach our operators. In the later stage of our development, we need to purchase new equipment, because HEIYAN's machine quality and service are very good, so we continue to cooperate with them. I wish HEIYAN machines can be sold to more customers.