Set of 12 LM8UU Linear Bearings for 3D Printer Prusa Mendel reprap 8mm x 15mm x 24mm Set of 12 pieces LM8UU Linear Motion Ball Bushing works with a 8mm Shafts, bearing inner Diameter is 8mm, bearing outer Diameter is 15mm and bearing Length is 24mm, Bearing has Built-in Rubber Seals.