Imported chips. Bell and SD series products are imported from France, assembled and produced in China, and the key components are imported. The production process is carried out according to the process requirements of French companies, and the cost performance is better than the original products. This series of products has compact structure, light weight and complete functions, and the number of starts per hour is more than 1200. Powerful logic control circuit, especially suitable for working environment with high degree of automation and frequent actions.