The kit contains 20 guide posts and 20 guide sleeves, sufficient in quantity, easy to use and replace. The product has high accuracy, the single piece concentricity is 0.005mm, and the combination concentricity is 0.03mm. These guide posts and guide sleeves are often used to that the mold moves with precise positioning. Overall ultravacuum heat treatment, with balanced hardness of HRC5862, not easy to wear. Using excellent 20Cr material, has good toughness and high strength, not easy to corrode for a long time. 1. These guide posts and guide sleeves are often used to that the mold moves with precise positioning. 2. The kit contains 20 guide posts and 20 guide sleeves, sufficient in quantity, easy to use and replace. 3. Using excellent 20Cr material, has good toughness and high strength, not easy to corrode for a long time. 4. Overall ultravacuum heat treatment, with balanced hardness of HRC5862, not easy to wear. 5. The product has high accuracy, the single piece concentricity is 0.005mm, and the combination concentricity is 0.03mm. Specification:Item Type: Guide Pin Sleeve Outer Diameter: . 10mm / 0.4inInner Diameter: . 7mm / 0.3inHead Height: . 10mm / 0.4in Total Height: . 20mm / 0.8in Carburized Layer: . 1mm / 0.04in Hardness: 58-62 Concentricity: 0.005 Fit Clearance: 0.03mm Note:Do not water, it will rust. Colour:Silver Material:Metal Package Contents: 20 x Guide Pin Sleeves Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.