Csk Bolt With Nut & Spring Washer, Part No: M20X80 Mm, Material Specification :- All Csk Bo Lts Are To Be Manufactured From High Grade Alloy Steel Confirming To Is: 6761 , Iso: 10642 ; Thread Iso Me Tric 4G-6G As Per Is: 4218, Iso:261. Mechanical Property Class 12.9 As Per Is: 1367, Iso: 898 Pt-I,(A). Hex Nut Confirming To Is:1364 (Part-3) Iso: 4032 Thread Iso Metric 6H As Per Is:4218, Iso:261. Mechanical Pr Operty Class : 8/10, As Per Is:1367, Iso:898 Pt Ii, Make-Unbrako Or Tvs Or Equivalent (B) Spring Washer-M Ake-Bbbb, As Per Is: 3063 Type B. [ Warranty Period: 30 Months After The Date Of Delivery ] ]