Factory Direct Sales - Anti-Loosening Nuts, Self-Locking Nuts, Serrated Nuts, Nylon Nuts, Press-Fit Screws PLC-M4, Full Specifications Available. Shenzhen Hengbo Precision Hardware Products Co., Ltd. specializes in the production and sales of American PEM, Southco press-fit screws and various products. A large inventory of commonly used parts is available. Welcome your new and old customers to send drawings for processing and customization. Look forward to establishing a good mutual trust and mutually beneficial business partnership. Welcome to send drawings or call for consultation. Phone: 0755-29941867