World Champion ACER Racing 3/16x3/8x1/8 Ball Bearing with dual teflon seals. This is a 3/16x3/8x1/8 ball bearing also known as a size R166 ball bearing. HSR cage technology and teflon sealed on both sides. Super fast and super smooth action. Price is for one 3/16x3/8x1/8 ball bearing as shown in the photo. Can be used in any application that requires a 3/16x3/8x1/8 bearing.