The GFM-1618-21 part is a high-performance plastic ball bearing from Igus. It is designed for use in applications that require high load capacity, low friction and longevity. The bearing consists of a polyamide cage, two races, and sixteen balls. The cage is designed to maintain the alignment of the balls and separate them from external debris. The bearing is corrosion-resistant and non-magnetic, making it ideal for applications in medical, robotics, automotive, and industrial fields. The GFM-1618-21 is designed with an inner and outer ring and it has a total width of 21 mm, an inner diameter of 16 mm, and an outer diameter of 18 mm.