*Sprocket kits include the following . *Stock size Primary Drive steel front sprocket . *Stock size Primary Drive steel rear sprocket. *Stock size Primary Drive 428 C chain . *All front and rear sprockets are manufactured to O.E.M., specs using high grade hardened steel . *All match original equipment exactly for perfect fit and size . *The C professional provides outstanding value in a chain without sacrificing strength or reliability . *Average tensile strength 5,400 lbs.