684ZZ Shielded Ball Bearing, Bearing IS made of bearing steel, each bearing has 2 metal shields to protect the bearing from dust or any possible contamination, the bearing is also pre-lubricated with grease. The 684zz bearing is a kind of versatile miniature bearing. It is widely used in precision instruments, mini motors, remote control models, etc. Material: Bearing Steel Size: 4 x 9 x 4 mm Color: Silver Model: 684ZZ Quantity: 100 Pcs Package Contents: 100 x Miniature Ball Bearings Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in a little different from the real thing. The measurement allowed error is +/- 1-3 cm.