12mm Low noise Linear Motion Bushing Solid Polymer Lm12uu Bearing 12x21x30mm12mm Linear Motion Bushing Low noise Solid Polymer Lm12uu Bearing Works with 12mm Shafts 12mmx21mmx30mm Low noise polymer LM12UU Linear Motion Ball Bushing works with a 12 mm Shafts, Size is 12mmx 21mmx 30mm, the inner Diameter is 12mm, the outer Diameter is 21mm and the Length is 30mm. Bearing has Built in Rubber Seals Polymer LM12UU Bearing Low noise Linear Motion Ball Bushing Number of Ball Circuit: 3 Size: 12mmx 21mmx 30mm Quantity: 1 Bearing