50 Pcs Self-Locking Nylon Nuts & 10 Pcs Ball Bearing Thread Size:(Female)M2 Product Name:Nylon Lock Nuts Material:Zinc Plated Colour: silver Nylon Lock Nuts: Hex head, female threaded inside, metal material, anti-loose hex nut. Used with a machine or cap screw for mechanically joining materials together. Used widely for matching screws or bolts. Made of metal material, full threaded rod. The most economical and most common form of Threaded Rod. Typically used by the plumbing and contracting trades. Used in maintenance departments in various applications. Height:3mm/0.12 inch Width Across Flats:4mm/0.16 inch Width Across Corners:4.3mm/0.17 inch Bearings: Material: metal model: 692 ZZ Size: 2 x 6 x 3mm(Inner Diameter x Outer Diameter x Thickness) Bearings reduce friction by providing smooth metal balls or rollers and a smooth inner and outer metal surface for the balls to roll against. These balls or rollers "bear" the load, allowing the device to spin smoothly. Package Included: 50 x Nylon Lock Nuts 10 x Bearings Only the above package content, other products are not included. Note: Light 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.