World Champion ACER Racing 6x16x5mm Ceramic Ball Bearing. This is a 6x16mm ceramic ball bearing also known as a size 696A ball bearing. Diamond polished Silicon Nitride (Si3N4) Balls, HSR cage technology and sealed on both sides. Lubricated with lightweight and 100% synthetic ACER Racing SIN Oil instead of thick grease for super fast and super smooth action.Price is for TWO bearings as shown in photo.