Outer diameter: 2.3-2.3, 2*2.3, 2-2, the outer diameter is 8mm, the length is 18mm, and the load is ready eight grams. The aspect fixing holes are M3. 2.3-3, 3*3, 3*3.17, 3.17*3.17 The outer diameter is 9mm, the size is 23mm, and the load is ready eight grams. The facet fixing holes are M3. 3.175-4, 4-3, 4-4, 4*2.3, outer diameter 9mm, size 23mm, weight about 7.5 grams, aspect solving holes are M3. 5-4, 3-5, 5-5, 4-6, 5-6, 6-6 The outer diameter is 11mm, the size is 23mm, and the load is ready 10 grams. The aspect fixing holes are M4. 5-8, 6-8, 8*8 outer diameter is 14mm, length is 35mm, weight is about 20g, facet solving hole is M4. (This mannequin has a circlip design and is fixed, so it is a bit tight, which is normal!) 8*10, 10*10 outer diameter 16mm, length 35mm, weight about 28 grams, facet fixing holes are M4.Product scope of application: The steel universal joint is appropriate for the use of the directly shaft of the motor, and is appropriate for the use of assorted metals equivalent to model cars, model boats, and robots!