Is Hainengda's back tone strict?

Strict. According to Tian Yan's inquiry. Hainengda mainly develops mine walkie-talkies and explosion-proof communication products and accessories. Because the development project needs to be kept secret, the callback is strict. Hainengda Communication Co., Ltd. is a global private listed company headquartered in Shenzhen, China. Established in 1993, Hainengda Communication Co., Ltd. is the world's leading provider of special communication and solutions, and is committed to providing customers in the fields of public safety, emergency, energy, transportation, industry and commerce with faster, safer and more interconnected communication equipment and solutions in daily work and critical moments, helping cities to be more efficient and safer.