12 size precision steel balls assortment kit contains: 180pcs1mm 160pcs2mm 160pcs2.5mm 100pcs3mm 100pcs3.5mm 100pcs4mm 100pcs4.5mm 100pcs5mm 60pcs5.5mm 60pcs6mm 40pcs7mm 40pcs8mm. Made of 304 Stainless Steel. Uniform size, high wear resistance, high precision, smooth , no burr, exquisite appearance. Widely used in auto parts, motorcycles, bicycles bearings, casters, drawer slides etc. It can also be used as a mixing balls. Used to stir paint, nail polish, etc The is coated with a small amount of grease to reduce friction when the bearing rotates and prevent and rust. reduce the damage to the machine and extend the service life. Storage box packaging. steel balls are sorted by size and stored in compartments of . Easy to identify and store. Note: due to different production batches, the plastic box style is random Colour: Silver Material: Stainless steel Size: 10.01x3.99x1.30 cm Package Contents: 1200 * 12 Size Stainless Steel Precision Steel Balls Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.