New!!! Specification: Material: Polyformaldehyde. Color: White. Package: 100pcs-1000pcs. Size:8mm/0.31"(+/-0.05mm). About color: There are slight difference between the picture and the real item caused by light brightness,hope you can understand. Description: -Polyformaldehyde plastic (also called polypropylene) is multi-purpose plastic and has established a position as an engineering plastic. -Bearing balls are used in applications such as drawer slides, precision bearings, pumps and valves, check valves, flow meters, and measurement instruments that operate in aggressive environments. -Polyformaldehyde bearing balls are specially useful for low load bearings, special valves, check valves, flotage valves, fluid level indicators, carburetors, flow meters, chemical, laboratory devices. Quantity: 100-1000Pcs (Optional)