Up for sale is a brand new pair (2 pieces) of Engine Position Sensors for Detroit Diesel Series 60 engines. Product Details:Part Number: 23527339Quantity: 2 Sensors included (Perfect for replacing both your TRS and SRS at the same time). Condition: Brand New, never installed. Markings on Sensors: Stamped with “Mexico” and batch/production codes 3440 and 3111. Fitment:These fit Detroit Diesel Series 60 engines (11.1L, 12.7L, and 14L) used in heavy-duty trucks. They function as both the Timing Reference Sensor (TRS) and the Synchronous Reference Sensor (SRS). Please verify your part number matches 23527339 before ordering.