OTC's Detroit Diesel 30 mm, 12 pt. socket ensures proper fit during nozzle removal and installation GM 6.2L and 6.5L Detroit Diesel engines. Built in 3/8 inch square drive and 7/8 inch hex permit easy access in tight quarters. Prevents damage to nozzle and related components. Value is at the core of the OTC tool and equipment portfolio. For a simple repair or the most complex drivability concern, these award-winning tools universally solve problems faster, and at better value, than any other product line available. Whether it's a specialty tool or unique piece of service equipment, OTC provides top solutions to modern automotive service challenges while increasing technicians' productivity and shop profits.