Product Description 1. Application: Fits For Mercedes Benz M270 Engine. For Mercedes Benz C177 W177 W176 W240 W246 X156. Please check make/mode/year before purchase. 2. Function: Used to turn the idler and replace the serpentine belt easily, helping you smoothly remove tension when dismantling the V-ribbed belt. 3. Direct Replacement: Alternative to JTC 4346, MM# 270589000700 both in function and performance. 4. Premium Material: Featured top high quality solid steel, constructed with slick black finish and red handle, durable and anti corrosion, repeatedly tested and gradually optimized to ensure its excellent performance and lasting service time. .