TruVativ 4 arm bolt kit suitable for Double with RockGuard or chainring guard. Made of steel. Bolt kit comes with 12.5 mm long nuts. Kit includes two sets of bolts: one set is 8 mm long, the other is 9.5 mm. RockGuard bolt position. Available in black colour.Bolt for rock guard or chainring guard,Made of steel,Includes two sets of bolts: 8 bolt of size 8 mm long and 4 bolts of size 9.5 mm length,12.5 mm nut length.