The customer hopes to replace old fluorescent lights at a shopping center in Singapore with LED lights with the old wire connection remaining unchanged. This requires that the LED light should be well compatible with the ballasts in the existing circuits. We asked the customer to send us samples of the ballasts, and use them as reference in product development. After thorough researches and experiments, we successfully developed a LED light that meets the expectation of the customer. The customer is so satisfied with the light sample after using it that the responsible person immediately ordered our products.