OTC's 5889 Rocker Arm Shaft Socket is a deep-well 12mm socket used to torque rocker arm nuts to OE specification. Specially designed socket features a stepped outside diameter for proper clearance and access to the fastener. Applications include Detroit Diesel Series 60 engines. Specifications: 12mm, 12pt socket; 1/2 inch square drive; high-strength, heat treated steel construction. Similar to J-44706. Made in the USA. Value is at the core of the OTC tool and equipment portfolio. Whether it's 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.