Hexagon Nut, Stopper Nut (Option) Part No. for Series 25AHexagon nut Basic type With cap Stopper nut Thread size M8 25-RB08J 25-RB08S 25-RBC08S M10 25-RB10J 25-RB10S 25-RBC10S M14 25-RB14J 25-RB14S 25-RBC14S M20 25-RB20J 25-RB20S 25-RBC20S M27 25-RB27J 25-RB27S 25-RBC27S Material: Special steel Treatment: Electroless nickel plating RJ RJ How to Order Series 25A-RJ Shock absorber/Soft type 0806 0604 H U Collision speed range H L O.D. thread size/Stroke Symbol 0604 0806 1007 1412 2015 2725 O.D. thread 6 mm 8 mm 10 mm 14 mm 20 mm 27 mm Stroke 4 mm 6 mm 7 mm 12 mm 15 mm 25 mm With cap Option 25A 25A Series compatible with secondary batteries . RJ0604: 0.05 to 1.0 m/s . RJ2725H: 0.05 to 1.5 m/s Hexagon nut 2 pcs. 3 pcs. . 2 pcs. 3 pcs. . Stopper nut . . . 1 pc. 1 pc. 1 pc. Symbol Nil J N S SJ SN Basic type With urethane cap Nil U 0.05 to 2 m/s 0.05 to 1 m/s . Specifications and dimensions for the 25A-series are the same as standard products. Shock Absorber Soft Type 101