This 800 series overlock sewing machine is a versatile machine suitable for sewing thin, medium and thick materials. Stronger adaptability to sewing various fabrics and closer to market demands. Complete models, 3, 4, 5 threads and related models, which can meet the special requirements of users to sew products. Strong versatility spare parts,general wearing parts all use standard universal parts. Simpler and faster replacement, maintenance and repair. Brand new integrated overall design, with a beautiful appearance and simple operation and adjustment. The original top cover design eliminates the defects of oil seepage and yellowing on the top cover. (applied patent)