1、Applicable Model: The engine brake adjustment tool is replacement for Detroit Diesel DD13 DD15 DD16 Engine. Please confirm whether it is consistent with the product you want before buying to avoid unnecessary return. 2、OE Number: The part numbers for reference are W470589042300 for 4.6mm tool and W470589022300 for 4.1mm tool. Please confirm whether it is consistent with the OE you need to avoid wrong buying and other problems. 3、Angled Feeler Gauge: The specially angled feeler gauge makes it easier to insert between the slave pistons and the exhaust valve adjusting screw. 4、Durable Construction: Made from high strength materials, this engine jake brake feeler gauge is built to withstand frequent use durable and reliable, ensuring long lasting use. 5、Fast and Efficient: This engine brake repair adjustment tool allows you to quickly and accurately measure valve clearance, time and effort saving.